Underwriting Agreement dated May 5, 2011

Exhibit 1.1

EXECUTION COPY

Mistras Group, Inc.

Common Stock

UNDERWRITING AGREEMENT

May 5, 2011

J.P. Morgan Securities LLC,

383 Madison Avenue,

New York, N.Y. 10179

Merrill Lynch, Pierce, Fenner & Smith Incorporated,

4 World Financial Center,

New York, N.Y. 10080

As Representatives (the “Representatives”) of the Several Underwriters,

Dear Sirs:

     1. Introductory. Mistras Group, Inc., a Delaware corporation (“Company”), agrees with the several Underwriters named in Schedule A hereto (“Underwriters”) to issue and sell to the several Underwriters 500,000 shares of its common stock, par value $0.01 per share (“Securities”), and the stockholder listed in Schedule B hereto (“Selling Stockholder”) agrees with the Underwriters to sell to the several Underwriters 2,764,401 outstanding shares of the Securities (such aggregate of 3,264,401 shares of Securities being hereinafter referred to as the “Firm Securities”). The Company also agrees to sell to the Underwriters, at the option of the Underwriters, an aggregate of not more than 489,660 additional shares (such 489,660 shares of Securities being hereinafter referred to as the “Optional Securities”) of its Securities, as set forth below. The Firm Securities and the Optional Securities are herein collectively called the “Offered Securities”; and the Firm Securities offered by the Company and the Optional Securities are herein collectively called the “Company Offered Securities”.

     2. Representations and Warranties of the Company and the Selling Stockholder. (a) The Company represents and warrants to, and agrees with, the several Underwriters that:

     (i) Filing and Effectiveness of Registration Statement; Certain Defined Terms. The Company has filed with the Commission a registration statement on Form S-3 (No. 333-173513) covering the registration of the Offered Securities under the Act, including a related preliminary prospectus or prospectuses. At any particular time, this initial registration statement, in the form then on file with the Commission, including all information contained in the registration statement (if any) pursuant to Rule 462(b) and then deemed to be a part of the initial registration statement, and all 430A Information and all 430C Information, that in any case has not then been superseded or modified, shall be referred to as the “Initial Registration Statement”. The Company may also have filed, or may file with the Commission, a Rule 462(b) registration statement covering the registration of Offered Securities. At any particular time, this Rule 462(b) registration statement, in the form then on file with the Commission, including the contents of the Initial Registration Statement incorporated by reference therein and including all 430A Information and all 430C

Information, that in any case has not then been superseded or modified, shall be referred to as the “Additional Registration Statement”.

     As of the time of execution and delivery of this Agreement, the Initial Registration Statement has been declared effective under the Act and is not proposed to be amended. Any Additional Registration Statement has or will become effective upon filing with the Commission pursuant to Rule 462(b) and is not proposed to be amended. The Offered Securities all have been or will be duly registered under the Act pursuant to the Initial Registration Statement and, if applicable, the Additional Registration Statement.

     For purposes of this Agreement:

     “430A Information”, with respect to any registration statement, means information included in a prospectus and retroactively deemed to be a part of such registration statement pursuant to Rule 430A(b).

     “430C Information”, with respect to any registration statement, means information included in a prospectus then deemed to be a part of such registration statement pursuant to Rule 430C.

     “Act” means the Securities Act of 1933, as amended.

     “Applicable Time” means 4:30 p.m. (Eastern time) on the date of this Agreement.

     “Closing Date” has the meaning defined in Section 3 hereof.

     “Commission” means the United States Securities and Exchange Commission.

     “Effective Time” with respect to the Initial Registration Statement or, if filed prior to the execution and delivery of this Agreement, the Additional Registration Statement means the date and time as of which such Registration Statement was declared effective by the Commission or has become effective upon filing pursuant to Rule 462(c). If an Additional Registration Statement has not been filed prior to the execution and delivery of this Agreement but the Company has advised the Representatives that it proposes to file one, “Effective Time” with respect to such Additional Registration Statement means the date and time as of which such Registration Statement is filed and becomes effective pursuant to Rule 462(b).

     “Exchange Act” means the Securities Exchange Act of 1934, as amended.

     “Final Prospectus” means the Statutory Prospectus that discloses the public offering price, other 430A Information and other final terms of the Offered Securities and otherwise satisfies Section 10(a) of the Act.

     “General Use Issuer Free Writing Prospectus” means any Issuer Free Writing Prospectus that is intended for general distribution to prospective investors, as evidenced by its being so specified in Schedule C to this Agreement.

     “Issuer Free Writing Prospectus” means any “issuer free writing prospectus”, as defined in Rule 433, relating to the Offered Securities in the form filed or required to be filed with the Commission or, if not required to be filed, in the form retained in the Company’s records pursuant to Rule 433(g).

     “Limited Use Issuer Free Writing Prospectus” means any Issuer Free Writing Prospectus that is not a General Use Issuer Free Writing Prospectus.

     The Initial Registration Statement and the Additional Registration Statement are referred to collectively as the “Registration Statements” and individually as a “Registration Statement”. A “Registration Statement” with reference to a particular time means the Initial Registration Statement and any Additional Registration Statement as of such time. A “Registration Statement” without reference to a time means such Registration Statement as of its Effective Time. For purposes of the foregoing definitions, 430A Information with respect to a Registration Statement shall be considered to be included in such Registration Statement as of the time specified in Rule 430A.

     “Rules and Regulations” means the rules and regulations of the Commission.

     “Securities Laws” means, collectively, the Sarbanes-Oxley Act of 2002 (“Sarbanes-Oxley”), the Act, the Exchange Act, the Rules and Regulations, the auditing principles, rules, standards and practices applicable to auditors of “issuers” (as defined in Sarbanes-Oxley) promulgated or approved by the Public Company Accounting Oversight Board and, as applicable, the rules of the New York Stock Exchange and the NASDAQ Stock Market (“Exchange Rules”).

     “Statutory Prospectus” with reference to a particular time means the prospectus included in a Registration Statement immediately prior to that time, including any 430A Information or 430C Information with respect to such Registration Statement. For purposes of the foregoing definition, 430A Information shall be considered to be included in the Statutory Prospectus as of the actual time that form of prospectus is filed with the Commission pursuant to Rule 424(b) or Rule 462(c) and not retroactively.

     Unless otherwise specified, a reference to a “rule” is to the indicated rule under the Act.

     (ii) Compliance with Securities Act Requirements. (i) (A) At their respective Effective Times, (B) on the date of this Agreement and (C) on each Closing Date, each of the Initial Registration Statement and the Additional Registration Statement (if any) conformed and will conform in all material respects to the requirements of the Act and (ii) on its date, at the time of filing of the Final Prospectus pursuant to Rule 424(b) or (if no such filing is required) at the Effective Time of the Additional Registration Statement in which the Final Prospectus is included, and on each Closing Date, the Final Prospectus will conform in all material respects to the requirements of the Act and the Rules and Regulations and will not include any untrue statement of a material fact or omit to state any material fact required to be stated therein or necessary to make the statements therein, in light of the circumstances under which they were made, not misleading. The preceding sentence does not apply to statements in or omissions from any such document based upon written information furnished to the Company by (a) any Underwriter through the Representatives specifically for use therein, it being understood and agreed that the only such information is that described as such in Section 8(c) hereof or (b) the Selling Stockholder specifically for use therein, it being understood and agreed that the only such information furnished by the Selling Stockholder (the “Selling Stockholder Information” of the Selling Stockholder) consists of the information with respect to the Selling Stockholder that appears in the table and the corresponding footnotes thereto, excluding any percentages, under the caption “Selling Stockholder” in the Final Prospectus and the General Disclosure Package.

     (iii) Ineligible Issuer Status. (i) At the time of the initial filing of the Initial Registration Statement and (ii) at the date of this Agreement, the Company was not and is not an “ineligible issuer,” as defined in Rule 405, including (x) the Company or any subsidiary of the Company in the preceding three years not having been convicted of a felony or misdemeanor or having been made the subject of a judicial or administrative decree or order as described in Rule 405 and (y) the Company in the preceding three years not having been the subject of a bankruptcy petition or insolvency or similar proceeding, not having had a registration statement be the subject of a proceeding under Section 8 of the Act and not being the subject of a proceeding under Section 8A of the Act in connection with the offering of the Offered Securities, all as described in Rule 405.

     (iv) General Disclosure Package. As of the Applicable Time, neither (i) the General Use Issuer Free Writing Prospectus(es) issued at or prior to the Applicable Time, the preliminary prospectus, dated May 2, 2011 (which is the most recent Statutory Prospectus distributed to investors generally) and the other information, if any, stated in Schedule C to this Agreement to be included in the general disclosure package, all considered together (collectively, the “General Disclosure Package”), nor (ii) any individual Limited Use Issuer Free Writing Prospectus, when considered together with the General Disclosure Package, included any untrue statement of a material fact or omitted to state any material fact necessary in order to make the statements therein, in the light of the circumstances under which they were made, not misleading. The preceding sentence does not apply to statements in or omissions from any Statutory Prospectus or any Issuer Free Writing Prospectus in reliance upon and in conformity with written information furnished to the Company by (a) any Underwriter through the Representatives specifically for use therein, it being understood and agreed that the only such information furnished by any Underwriter consists of the information described as such in Section 8(c) hereof or (b) the Selling Stockholder specifically for use therein, it being understood and agreed that the only such information furnished by the Selling Stockholder is the Selling Stockholder Information.

     (v) Issuer Free Writing Prospectuses. Each Issuer Free Writing Prospectus, as of its issue date and at all subsequent times through the completion of the public offer and sale of the Offered Securities or until any earlier date that the Company notified or notifies the Representatives as described in the next sentence, did not, does not and will not include any information that conflicted, conflicts or will conflict with the information then contained in the Registration Statement. If at any time following issuance of an Issuer Free Writing Prospectus there occurred or occurs an event or development as a result of which such Issuer Free Writing Prospectus conflicted or would conflict with the information then contained in the Registration Statement or as a result of which such Issuer Free Writing Prospectus, if republished immediately following such event or development, would include an untrue statement of a material fact or omitted or would omit to state a material fact necessary in order to make the statements therein, in the light of the circumstances under which they were made, not misleading, (i) the Company has promptly notified or will promptly notify the Representatives and (ii) the Company has promptly amended or will promptly amend or supplement such Issuer Free Writing Prospectus to eliminate or correct such conflict, untrue statement or omission. The foregoing two sentences do not apply to statements in or omissions from any Issuer Free Writing Prospectus in reliance upon and in conformity with written information furnished to the Company by any Underwriter through the Representatives specifically for use therein, it being understood and agreed that the only such information furnished by (a) any Underwriter consists of the information described as such in Section 8(c) hereof or (b) the Selling Stockholder specifically for use therein, it being understood and agreed that the only such information furnished by the Selling Stockholder is the Selling Stockholder Information.

     (vi) Good Standing of the Company. The Company has been duly incorporated and is existing and in good standing under the laws of the State of Delaware, with power and authority (corporate and other) to own its properties and conduct its business as described in the General Disclosure Package; and the Company is duly qualified to do business as a foreign corporation in good standing in all other jurisdictions in which its ownership or lease of property or the conduct of its business requires such qualification, except where the failure to be so qualified or be in good standing would not, individually or in the aggregate, have a material adverse effect on the condition (financial or otherwise), results of operations, business or properties of the Company and its subsidiaries taken as whole (“Material Adverse Effect”).

     (vii) Subsidiaries. Each subsidiary of the Company that meets the definition in Rule 1-02(w) of Regulation S-X (each a “Significant Subsidiary” and collectively, the “Significant Subsidiaries”) is listed in Schedule D to this Agreement. Each of the Significant Subsidiaries has been duly incorporated, formed or organized and is existing and in good standing under the laws of the jurisdiction of its incorporation, formation or organization with power and authority (corporate and other) to own its properties and conduct its business as described in the General

Disclosure Package; and each Significant Subsidiary is duly qualified to do business as a foreign entity in good standing in all other jurisdictions in which its ownership or lease of property or the conduct of its business requires such qualification, except where the failure to be so qualified or be in good standing would not reasonably be expected to, individually or in the aggregate, have a Material Adverse Effect; all of the issued and outstanding equity interests or capital stock of each subsidiary of the Company have been duly authorized and validly issued and are fully paid and nonassessable; and the equity interests or capital stock of each Significant Subsidiary owned by the Company, directly or through subsidiaries, are owned free from liens, encumbrances and defects, except for such liens and encumbrances (A) imposed under the Company’s second amended and restated credit agreement, dated as of July 22, 2009, with Bank of America, N.A., JPMorgan Chase Bank, N.A., TD Bank, N.A. and Capital One, N.A., as amended as of December 14, 2009, (B) as would not reasonably be expected to, individually or in the aggregate, have a Material Adverse Effect and (C) as disclosed in the General Disclosure Package or the Final Prospectus.

     (viii) Offered Securities; Capitalization. The Offered Securities and all other outstanding shares of capital stock of the Company have been duly authorized; the authorized equity capitalization of the Company is as set forth in the General Disclosure Package; all outstanding shares of capital stock of the Company are, and, when the Company Offered Securities have been delivered and paid for in accordance with this Agreement on each Closing Date, such Company Offered Securities will have been, validly issued, fully paid and nonassessable, and will conform to the information in the General Disclosure Package and to the description of such Offered Securities contained in the Final Prospectus; the stockholders of the Company have no preemptive rights with respect to the Securities; and none of the outstanding shares of capital stock of the Company have been issued in violation of any preemptive or similar rights of any security holder.

     (ix) No Finder’s Fee. Except as disclosed in the General Disclosure Package and as contemplated by this Agreement, there are no contracts, agreements or understandings between the Company and any person that would give rise to a valid claim against the Company or any Underwriter for a brokerage commission, finder’s fee or other like payment in connection with this offering.

     (x) Registration Rights. Except as disclosed in the General Disclosure Package, there are no contracts, agreements or understandings between the Company and any person granting such person the right to require the Company to file a registration statement under the Act with respect to any securities of the Company owned or to be owned by such person or to require the Company to include such securities in the securities registered pursuant to a Registration Statement or in any securities being registered pursuant to any other registration statement filed by the Company under the Act (collectively, “registration rights”), and any person to whom the Company has granted registration rights has agreed not to exercise such rights until after the expiration of the Lock-Up Period referred to in Section 5(k) hereof.

     (xi) Listing. On or prior to the Closing Date, the Offered Securities will have been approved for listing on the New York Stock Exchange, subject to notice of issuance.

     (xii) Absence of Further Requirements. No consent, approval, authorization, or order of, or filing or registration with, any person (including any governmental agency or body or any court) is required to be obtained or made by the Company for the consummation of the transactions contemplated by this Agreement in connection with the sale of the Offered Securities, except (A) for such consents, approvals, authorizations, orders or filings obtained or made prior to the date hereof or that will have been obtained prior to the First Closing Date, (B) for the filing of the Registration Statements, as applicable, and the order of the Commission declaring the Registration Statements effective, (C) such as may be required under United States federal or state securities laws and (D) for those as to which the failure to obtain or make would not reasonably be expected to, individually or in the aggregate, have a material adverse effect on the ability of the Company to execute, deliver and perform the transactions contemplated by this Agreement.

     (xiii) Title to Property. Except as disclosed in the General Disclosure Package, the Company and the Significant Subsidiaries have good and marketable title to all real properties and all other properties and assets owned by them, in each case free from liens, charges, encumbrances and defects, except such liens, charges, encumbrances and defects, that would, individually or in the aggregate, have a Material Adverse Effect, and, except as disclosed in the General Disclosure Package, the Company and the Significant Subsidiaries hold all leased real or personal property under valid and enforceable leases with no terms or provisions that would materially interfere with the use made or to be made thereof by them, other than those exceptions that would not, individually or in the aggregate, have a Material Adverse Effect.

     (xiv) Absence of Defaults and Conflicts Resulting from Transaction. The execution, delivery and performance of this Agreement, and the issuance and sale of the Company Offered Securities, and the sale by the Selling Stockholder of the Firm Securities to be sold by it, will not result in a breach or violation of (A) any of the terms and provisions of, or constitute a default or a Debt Repayment Triggering Event (as defined below) under, or result in the imposition of any lien, charge or encumbrance upon any property or assets of the Company or any of the Significant Subsidiaries pursuant to, the charter or by-laws (or similar organizational documents) of the Company or any of the Significant Subsidiaries, (B) any statute, rule, regulation or order of any governmental agency or body or any court, domestic or foreign, having jurisdiction over the Company or any of its subsidiaries or any of their properties, or (C) any agreement or instrument to which the Company or any of its subsidiaries is a party or by which the Company or any of its subsidiaries is bound or to which any of the properties of the Company or any of its subsidiaries is subject, except with respect to (B) and (C) only, for such breaches, violations or defaults that would not reasonably be expected to, individually or in the aggregate, result in a Material Adverse Effect; a “Debt Repayment Triggering Event” means any event or condition that gives, or with the giving of notice or lapse of time would give, the holder of any note, debenture, or other evidence of indebtedness (or any person acting on such holder’s behalf) the right to require the repurchase, redemption or repayment of all or a portion of such indebtedness by the Company or any of its subsidiaries.

     (xv) Absence of Existing Defaults and Conflicts. Neither the Company nor any of its subsidiaries is in violation of its respective charter or by-laws (or similar organizational documents) or in default (or with the giving of notice or lapse of time would be in default) under any existing obligation, agreement, covenant or condition contained in any indenture, loan agreement, mortgage, lease or other agreement or instrument to which any of them is a party or by which any of them is bound or to which any of the properties of any of them is subject, except such defaults that would not reasonably be expected to, individually or in the aggregate, result in a Material Adverse Effect.

     (xvi) Authorization of Agreement. This Agreement has been duly authorized, executed and delivered by the Company.

     (xvii) Possession of Licenses and Permits. (A) The Company and the Significant Subsidiaries possess, and are in compliance with the terms of, all adequate certificates, authorizations, franchises, licenses and permits (“Licenses”) necessary or material to the conduct of the business that the Company currently conducts and neither the Company nor any of the Significant Subsidiaries has received any written notice of proceedings relating to the revocation or modification of any such Licenses that, if determined adversely to the Company or any of its subsidiaries, would reasonably be expected to, individually or in the aggregate, have a Material Adverse Effect and (B) with respect to business that the Company proposes to conduct in the General Disclosure Package, to the Company’s knowledge such Licenses can be obtained on customary terms and conditions, and neither the Company nor the Significant Subsidiaries has received any notice of proceedings relating to the revocation or modification of any such Licenses that, if determined adversely to the Company or any of its subsidiaries would, individually or in the aggregate, have a Material Adverse Effect.

     (xviii) Absence of Labor Dispute. Except as disclosed in the General Disclosure Package, no labor dispute with the employees of the Company or any of its subsidiaries exists or, to the knowledge of the Company, is imminent that could have a Material Adverse Effect.

     (xix) Possession of Intellectual Property. The Company and its subsidiaries own, possess or can acquire on reasonable terms sufficient trademarks, trade names, patent rights, copyrights, domain names, licenses, approvals, trade secrets, inventions, technology, know-how and other intellectual property and similar rights, including registrations and applications for registration thereof (collectively, “Intellectual Property Rights”) necessary or material to the conduct of the business now conducted or proposed in the General Disclosure Package to be conducted by them, have not received any notice of infringement of or conflict with asserted rights of others with respect to any Intellectual Property Rights that if determined adversely to the Company or any of its subsidiaries, would individually or in the aggregate, have a Material Adverse Effect, and the expected expiration of any such Intellectual Property Rights would not, individually or in the aggregate, have a Material Adverse Effect. Except as disclosed in the General Disclosure Package, there is no pending or, to the Company’s knowledge, threatened action, suit, proceeding or claim by others that the Company or any subsidiary infringes, misappropriates or otherwise violates or conflicts with any Intellectual Property Rights or other proprietary rights of others and the Company is unaware of any fact which would form a reasonable basis for any such claim.

     (xx) Environmental Laws. Except as disclosed in the General Disclosure Package, neither the Company nor any of its subsidiaries is in violation of any statute, any rule, regulation, decision or order of any governmental agency or body or any court, domestic or foreign, relating to the use, disposal or release of hazardous or toxic substances or relating to the protection or restoration of the environment or human exposure to hazardous or toxic substances (collectively, “environmental laws”), owns or operates any real property contaminated with any substance that is subject to any environmental laws, is liable for any off-site disposal or contamination pursuant to any environmental laws, or is subject to any claim relating to any environmental laws, which violation, contamination, liability or claim would individually or in the aggregate have a Material Adverse Effect; and the Company is not aware of any pending investigation which might lead to such a claim.

     (xxi) Accurate Disclosure. The statements in the General Disclosure Package and the Final Prospectus under the headings “Material U.S. Federal Tax Consequences for Non-U.S. Holders of Common Stock”, “Description of Capital Stock”, “Business—Legal Proceedings” and “Certain Relationships and Related Transactions, and Director Independence”, insofar as such statements summarize legal matters, agreements, documents or proceedings discussed therein, are, in all material respects, accurate and fair summaries of such legal matters, agreements, documents or proceedings and present the information required to be shown.

     (xxii) Absence of Manipulation. The Company has not taken, directly or indirectly, any action that is designed to or that has constituted or that would reasonably be expected to cause or result in the stabilization or manipulation of the price of any security of the Company to facilitate the sale or resale of the Offered Securities, except as disclosed in the General Disclosure Package and Final Prospectus.

     (xxiii) Statistical and Market-Related Data. Any third-party statistical and market-related data included in a Registration Statement, a Statutory Prospectus or the General Disclosure Package are based on or derived from sources that the Company believes to be reliable and accurate.

     (xxiv) Internal Controls. Except as set forth in the General Disclosure Package, the Company maintains a system of internal controls, including, but not limited to, disclosure controls and procedures, internal controls over accounting matters and financial reporting, an internal audit function and legal and regulatory compliance controls (collectively, “Internal Controls”) that comply with the Securities Laws and are sufficient to provide reasonable assurances that (i) transactions are executed in accordance with management’s general or specific authorizations, (ii) transactions are recorded as necessary to permit preparation of financial statements in

conformity with U.S. Generally Accepted Accounting Principles and to maintain accountability for assets, (iii) access to assets is permitted only in accordance with management’s general or specific authorization, and (iv) the recorded accountability for assets is compared with the existing assets at reasonable intervals and appropriate action is taken with respect to any differences. The Internal Controls are overseen by the Audit Committee (the “Audit Committee”) of the Company’s Board of Directors (the “Board”) in accordance with Exchange Rules. Except as disclosed in the General Disclosure Package, the Company has not publicly disclosed or reported to the Audit Committee or the Board, since the date of the Company’s most recently audited fiscal year, and the Company does not reasonably expect to publicly disclose or report to the Audit Committee or the Board within the next 90 days from the date of this Agreement, a material weakness, change in Internal Controls or fraud involving management or other employees who have a significant role in Internal Controls (each, an “Internal Control Event”), any violation of, or failure to comply with, the Securities Laws, or any matter involving internal controls, which in all instances, if determined adversely, would have a Material Adverse Effect, and is not aware of any significant deficiency that has not previously been publicly disclosed, except as would not have a Material Adverse Effect.

     (xxv) Absence of Accounting Issues. The Board of Directors of the Company has confirmed to the Chief Executive Officer or Chief Financial Officer that, except as set forth in the General Disclosure Package, the Board is not reviewing or investigating, and neither the Company’s independent auditors nor its internal auditors have recommended that the Board review or investigate, (i) adding to, deleting, changing the application of, or changing the Company’s disclosure with respect to, any of the Company’s material accounting policies; (ii) any matter which could result in a restatement of the Company’s financial statements for any annual or interim period during the current or prior three fiscal years; or (iii) any Internal Control Event.

     (xxvi) Litigation. Except as disclosed in the General Disclosure Package, there are no pending actions, suits or proceedings (including any inquiries or investigations by any court or governmental agency or body, domestic or foreign) against or affecting the Company, any of the Significant Subsidiaries or any of their respective properties that, if determined adversely to the Company or any of the Significant Subsidiaries, would reasonably be expected to, individually or in the aggregate, have a Material Adverse Effect, or would materially and adversely affect the ability of the Company to perform its obligations under this Agreement, or which are otherwise material in the context of the sale of the Offered Securities; and no such actions, suits or proceedings (including any inquiries or investigations by any court or governmental agency or body, domestic or foreign) are pending or, to the Company’s knowledge, threatened.

     (xxvii) Financial Statements. The financial statements included in each Registration Statement and the General Disclosure Package present fairly, in all material respects, the financial position of the Company and its consolidated subsidiaries as of the dates shown and their results of operations and cash flows for the periods shown, and such financial statements have been prepared in conformity with United States generally accepted accounting principles applied on a consistent basis; and the schedules included in each Registration Statement present fairly the information required to be stated therein.

     (xxviii) No Material Adverse Change in Business. Except as disclosed in the General Disclosure Package, since the end of the period covered by the latest audited financial statements included in the General Disclosure Package (i) there has been no change, nor any development or event involving a prospective change, in the condition (financial or otherwise), results of operations, business, or properties of the Company and its subsidiaries, taken as a whole, that is material and adverse, (ii) except as disclosed in or contemplated by the General Disclosure Package, there has been no dividend or distribution of any kind declared, paid or made by the Company on any class of its capital stock and (iii) except as disclosed in or contemplated by the General Disclosure Package, there has been no material adverse change in the capital stock, short-term indebtedness, long-term indebtedness, net current assets or net assets of the Company and the Significant Subsidiaries.

     (xxix) Investment Company Act. The Company is not and, after giving effect to the offering and sale of the Offered Securities by the Company and the application of the proceeds thereof as described in the General Disclosure Package, will not be an “investment company” as defined in the Investment Company Act of 1940 (the “Investment Company Act”).

     (xxx) Ratings. No “nationally recognized statistical rating organization” as such term is defined for purposes of Rule 436(g)(2) (i) has imposed (or has informed the Company that it is considering imposing) any condition (financial or otherwise) on the Company’s retaining any rating assigned to the Company or any securities of the Company or (ii) has indicated to the Company that it is considering any of the actions described in Section 7(c)(ii) hereof.

     (xxxi) PFIC Status. No subsidiary of the Company created or organized outside of the United States was a “passive foreign investment company” (“PFIC”) as defined in Section 1297 of the United States Internal Revenue Code of 1986, as amended (the “Code”), for its most recently completed taxable year and, based on the relevant subsidiary’s current projected income, assets and activities, it does not expect to be classified as a PFIC for any subsequent taxable year.

     (xxxii) Compliance with Various Laws and Regulations. Each of the Company, the Significant Subsidiaries, their affiliates and, to the Company’s knowledge, any of their respective officers, directors, supervisors, managers, agents, or employees, has not violated, and its participation in the offering will not violate, each of the following laws: (a) anti-bribery laws, including but not limited to, any applicable law, rule, or regulation of any locality, including but not limited to any law, rule, or regulation promulgated to implement the OECD Convention on Combating Bribery of Foreign Public Officials in International Business Transactions, signed December 17, 1997, including the U.S. Foreign Corrupt Practices Act of 1977 or any other law, rule or regulation of similar purpose and scope, (b) anti-money laundering laws, including but not limited to, applicable Federal, state, international, foreign or other laws, regulations or government guidance regarding anti-money laundering, including, without limitation, Title 18 U.S. Code Sections 1956 and 1957, the Patriot Act, the Bank Secrecy Act, and international anti-money laundering principals or procedures by an intergovernmental group or organization, such as the Financial Action Task Force on Money Laundering, of which the United States is a member and with which designation the United States representative to the group or organization continues to concur, all as amended, and any Executive order, directive, or regulation pursuant to the authority of any of the foregoing, or any orders or licenses issued thereunder or (c) laws and regulations imposing U.S. economic sanctions measures, including, but not limited to, the International Emergency Economic Powers Act, the Trading with the Enemy Act, the United Nations Participation Act and the Syria Accountability and Lebanese Sovereignty Act, all as amended, and any Executive Order, directive, or regulation pursuant to the authority of any of the foregoing, including the regulations of the United States Treasury Department set forth under 31 CFR, Subtitle B, Chapter V, as amended, or any orders or licenses issued thereunder.

     (xxxiii) Tax Filings. The Company and its subsidiaries have filed all federal, state, local and non-U.S. tax returns that are required to be filed or have requested extensions thereof (except in any case in which the failure so to file would not have a Material Adverse Effect); and, except as set forth in the General Disclosure Package, the Company and its subsidiaries have paid all taxes (including any assessments, fines or penalties) required to be paid by them, except for any such taxes, assessments, fines or penalties currently being contested in good faith or as would not, individually or in the aggregate, have a Material Adverse Effect.

     (xxxiv) Insurance. The Company and its subsidiaries are insured by insurers with appropriately rated claims paying abilities against such losses and risks and in such amounts as are customary for the businesses in which they are engaged; all policies of insurance insuring the Company or any of its subsidiaries or their respective businesses, assets, employees, officers and directors are in full force and effect; the Company and its subsidiaries are in compliance with the terms of such policies and instruments in all material respects; and there are no claims by the Company or any of its subsidiaries under any such policy or instrument as to which any insurance company is denying liability or defending under a reservation of rights clause; the Company has not been refused any

insurance coverage sought or applied for; neither the Company nor any such subsidiary has any reason to believe that it will not be able to renew its existing insurance coverage as and when such coverage expires or to obtain similar coverage from similar insurers as may be necessary to continue its business at a cost that would not have a Material Adverse Effect, except as set forth in or contemplated in the General Disclosure Package.

     (b) The Selling Stockholder represents and warrants to, and agrees with, the several Underwriters that:

     (i) Title to Securities. The Selling Stockholder has and on each Closing Date hereinafter mentioned will have valid and unencumbered title to the Offered Securities to be delivered by the Selling Stockholder on such Closing Date and full right, power and authority to enter into this Agreement and to sell, assign, transfer and deliver the Offered Securities to be delivered by the Selling Stockholder on such Closing Date hereunder; and upon the delivery of and payment for the Offered Securities on each Closing Date hereunder the several Underwriters will acquire valid and unencumbered title to the Offered Securities to be delivered by the Selling Stockholder on such Closing Date.

     (ii) Absence of Further Requirements. No consent, approval, authorization or order of, or filing with, any person (including any governmental agency or body or any court) is required to be obtained or made by the Selling Stockholder for the consummation of the transactions contemplated by this Agreement in connection with the offering and sale of the Offered Securities sold by the Selling Stockholder, except (A) for such consents, approvals, authorizations, orders or filings obtained or made prior to the date hereof or that will have been obtained prior to the First Closing Date, (B) for the filing of the Registration Statements, as applicable, and the order of the Commission declaring the Registration Statements effective, (C) such as have been obtained and made under the Act and such as may be required under federal and state securities laws; and (D) for those as to which the failure to obtain or make would not reasonably be expected to, individually or in the aggregate, have an adverse effect on the ability of the Selling Stockholder to execute, deliver and perform the transactions contemplated by this Agreement;

     (iii) Absence of Defaults and Conflicts Resulting from Transaction. The execution, delivery and performance of this Agreement and the consummation of the transactions herein contemplated will not result in a breach or violation of any of the terms and provisions of, or constitute a default under, or result in the imposition of any lien, charge or encumbrance upon any property or assets of the Selling Stockholder pursuant to, (A) any statute, any rule, regulation or order of any governmental agency or body or any court having jurisdiction over the Selling Stockholder or any of its properties, (B) any agreement or instrument to which the Selling Stockholder is a party or by which the Selling Stockholder is bound or to which any of the properties of the Selling Stockholder is subject, or (C) the organizational documents of the Selling Stockholder; except in the case of (A) and (B) only, for such breach, violation, or default that would not reasonably be expected to, individually or in the aggregate, have a material adverse effect on the ability of the Selling Stockholder to consummate the transactions contemplated by this Agreement.

     (iv) Compliance with Securities Act Requirements. On its date, at the time of filing of the Final Prospectus pursuant to Rule 424(b) or (if no such filing is required) at the Effective Time of the Additional Registration Statement in which the Final Prospectus is included, and on each Closing Date, the Final Prospectus will not include any untrue statement of a material fact or omit to state any material fact required to be stated therein or necessary to make the statements therein, in light of the circumstances under which they were made, not misleading. The preceding sentence applies only to the extent that any such statement in or omissions from any such document is made in reliance upon and in conformity with written information furnished to the Company by the Selling Stockholder specifically for use therein, it being understood and agreed that the only such information furnished by the Selling Stockholder is the Selling Stockholder Information.

     (v) No Undisclosed Material Information. The sale of the Offered Securities by the Selling Stockholder pursuant to this Agreement is not prompted by any material information concerning the Company or any of the Significant Subsidiaries that is not set forth the General Disclosure Package.

     (vi) Authorization of Agreement. This Agreement has been duly authorized, executed and delivered by the Selling Stockholder.

     (vii) No Finder’s Fee. Except as disclosed in the General Disclosure Package or as contemplated by this Agreement, there are no contracts, agreements or understandings between the Selling Stockholder and any person that would give rise to a valid claim against the Selling Stockholder or any Underwriter for a brokerage commission, finder’s fee or other like payment in connection with the issuance or sale of Offered Securities.

     (viii) Absence of Manipulation. The Selling Stockholder has not taken, directly or indirectly, any action that is designed to or that has constituted or that would reasonably be expected to cause or result in the stabilization or manipulation of the price of any security of the Company to facilitate the sale or resale of the Offered Securities.

     3. Purchase, Sale and Delivery of Offered Securities. On the basis of the representations, warranties and agreements and subject to the terms and conditions set forth herein, the Company and the Selling Stockholder agree, severally and not jointly, to sell to each Underwriter, and each Underwriter agrees, severally and not jointly, to purchase from the Company and the Selling Stockholder, at a purchase price of $15.20 per share, that number of Firm Securities (rounded up or down, as determined by the Representatives in their discretion, in order to avoid fractions) obtained by multiplying 500,000 Firm Securities in the case of the Company and the number of Firm Securities set forth opposite the name of the Selling Stockholder in Schedule B hereto, in the case of the Selling Stockholder, in each case by a fraction the numerator of which is the number of Firm Securities set forth opposite the name of such Underwriter in Schedule A hereto and the denominator of which is the total number of Firm Securities.

     The Company and the Selling Stockholder will deliver the Firm Securities to or as instructed by the Representatives for the accounts of the several Underwriters in a form reasonably acceptable to the Representatives against payment of the purchase price by the Underwriters in Federal (same day) funds by official bank check or checks or wire transfer to an account at a bank acceptable to the Representatives drawn to the order of the Company in the case of shares of the Firm Securities sold by the Company, and to the order of the Selling Stockholder in the case of the Firm Securities sold by the Selling Stockholder, at the office of Cravath, Swaine & Moore LLP, at 10:00 A.M., New York time, on May 11, 2011, or at such other time not later than seven full business days thereafter as the Representatives and the Company determine, such time being herein referred to as the “First Closing Date”. For purposes of Rule 15c6-1 under the Securities Exchange Act of 1934, the First Closing Date (if later than the otherwise applicable settlement date) shall be the settlement date for payment of funds and delivery of securities for all the Offered Securities sold pursuant to the offering. The Firm Securities so to be delivered or evidence of their issuance will be made available for checking at the above office of Cravath, Swaine & Moore LLP at least 24 hours prior to the First Closing Date.

     In addition, upon written notice from the Representatives given to the Company from time to time not more than 30 days subsequent to the date of the Final Prospectus, the Underwriters may purchase all or less than all of the Optional Securities at the purchase price per Security to be paid for the Firm Securities. The Company agrees to sell to the Underwriters such Optional Securities. Such Optional Securities shall be purchased from the Company for the account of each Underwriter in the same proportion as the number of Firm Securities set forth opposite such Underwriter’s name bears to the total number of Firm Securities (subject to adjustment by the Representatives to eliminate fractions) and may be purchased by the Underwriters only for the purpose of covering over-allotments made in connection with the sale of the Firm Securities. No Optional Securities shall be sold or delivered unless the Firm Securities previously have been, or simultaneously are, sold and delivered. The right to purchase the Optional Securities or any portion

thereof may be exercised from time to time and to the extent not previously exercised may be surrendered and terminated at any time upon notice by the Representatives to the Company.

     Each time for the delivery of and payment for the Optional Securities, being herein referred to as an “Optional Closing Date”, which may be the First Closing Date (the First Closing Date and each Optional Closing Date, if any, being sometimes referred to as a “Closing Date”), shall be determined by the Representatives but shall be not earlier than two business days and not later than five full business days after written notice of election to purchase Optional Securities is given. The Company will deliver the Optional Securities being purchased on each Optional Closing Date to or as instructed by the Representatives for the accounts of the several Underwriters in a form reasonably acceptable to the Representatives, against payment by the Underwriters of the purchase price therefore in Federal (same day) funds by official bank check or checks or wire transfer to an account at a bank acceptable to the Representatives drawn to the order of the Company at the office of Cravath, Swaine & Moore LLP. The Optional Securities being purchased on each Optional Closing Date or evidence of their issuance will be made available for checking at the above office of Cravath, Swaine & Moore LLP at a reasonable time in advance of such Optional Closing Date.

     4. Offering by Underwriters. It is understood that the several Underwriters propose to offer the Offered Securities for sale to the public as set forth in the Final Prospectus.

     5. Certain Agreements of the Company and the Selling Stockholder. The Company agrees with the several Underwriters and the Selling Stockholder that:

     (a) Additional Filings. Unless filed pursuant to Rule 462(c) as part of the Additional Registration Statement in accordance with the next sentence, the Company will file the Final Prospectus, in a form approved by the Representatives with the Commission pursuant to and in accordance with Rule 424(b) not later than the second business day following the execution and delivery of this Agreement. The Company will advise the Representatives promptly of any such filing pursuant to Rule 424(b) and provide satisfactory evidence to the Representatives of such timely filing. If an Additional Registration Statement is necessary to register a portion of the Offered Securities under the Act but the Effective Time thereof has not occurred as of the execution and delivery of this Agreement, the Company will file the additional registration statement or, if filed, will file a post-effective amendment thereto with the Commission pursuant to and in accordance with Rule 462(b) on or prior to 10:00 P.M., New York time, on the date of this Agreement or, if earlier, on or prior to the time the Final Prospectus is finalized and distributed to any Underwriter, or will make such filing at such later date as shall have been consented to by the Representatives.

     (b) Filing of Amendments: Response to Commission Requests. The Company will promptly advise the Representatives of any proposal to amend or supplement at any time the Initial Registration Statement, any Additional Registration Statement or any Statutory Prospectus and will not effect such amendment or supplementation without the Representatives’ consent, which consent shall not be unreasonably withheld; and the Company will also advise the Representatives promptly of (i) the effectiveness of any Additional Registration Statement (if its Effective Time is subsequent to the execution and delivery of this Agreement), (ii) any amendment or supplementation of a Registration Statement or any Statutory Prospectus, (iii) any request by the Commission or its staff for any amendment to any Registration Statement, for any supplement to any Statutory Prospectus or for any additional information, (iv) the institution by the Commission of any stop order proceedings in respect of a Registration Statement or the threatening of any proceeding for that purpose, and (v) the receipt by the Company of any notification with respect to the suspension of the qualification of the Offered Securities in any jurisdiction or the institution or threatening of any proceedings for such purpose. The Company will use its commercially reasonable efforts to prevent the issuance of any such stop order or the suspension of any such qualification and, if issued, to obtain as soon as possible the withdrawal thereof.

     (c) Continued Compliance with Securities Laws. If, at any time when a prospectus relating to the Offered Securities is (or but for the exemption in Rule 172 would be) required to be delivered under the Act by any Underwriter or dealer, any event occurs as a result of which the Final Prospectus as then amended or supplemented would include an untrue statement of a material fact or omit to state any material fact necessary to make the statements therein, in the light of the circumstances under which they were made, not misleading, or if it is necessary at any time to amend the Registration Statement or supplement the Final Prospectus to comply with the Act, the Company will promptly notify the Representatives of such event and will promptly prepare and file with the Commission and furnish, at its own expense, to the Underwriters and the dealers and any other dealers upon request of the Representatives, an amendment or supplement which will correct such statement or omission or an amendment which will effect such compliance. Neither the Representatives’ consent to, nor the Underwriters’ delivery of, any such amendment or supplement shall constitute a waiver of any of the conditions set forth in Section 7 hereof.

     (d) Rule 158. As soon as practicable, but not later than the Availability Date (as defined below), the Company will make generally available to its security holders an earnings statement covering a period of at least 12 months beginning after the Effective Date of the Initial Registration Statement (or, if later, the Effective Time of the Additional Registration Statement) which will satisfy the provisions of Section 11(a) of the Act and Rule 158 under the Act. For the purpose of the preceding sentence, “Availability Date” means the day after the date the Company is required to file its Form 10-Q for the fourth fiscal quarter following the fiscal quarter that includes such Effective Time on which the Company is required to file its Form 10-Q for such fiscal quarter except that, if such fourth fiscal quarter is the last quarter of the Company’s fiscal year, “Availability Date” means the day after the end of such fourth fiscal quarter on which the Company is required to file its Form 10-K.

     (e) Furnishing of Prospectuses. The Company will furnish to the Representatives copies of each Registration Statement (3 of which will be signed and will include all exhibits), each related Statutory Prospectus, and, so long as a prospectus relating to the Offered Securities is (or but for the exemption in Rule 172 would be) required to be delivered under the Act, the Final Prospectus and all amendments and supplements to such documents, in each case in such quantities as the Representatives request. The Final Prospectus shall be so furnished on or prior to 3:00 P.M., New York time, on the business day following the execution and delivery of this Agreement. All other such documents shall be so furnished as soon as available. The Company will pay the expenses of printing and distributing to the Underwriters all such documents.

     (f) Blue Sky Qualifications. The Company will arrange for the qualification of the Offered Securities for sale under the laws of such jurisdictions as the Representatives designate and will continue such qualifications in effect so long as required for the distribution of the Offered Securities by the Underwriters; provided that the Company will not be required to (i) qualify as a foreign corporation or other entity as a dealer in securities in such jurisdiction, (ii) file any general consent to service of process in any such jurisdiction, or (iii) subject itself to taxation in any such jurisdiction if it is not otherwise so subject.

     (g) Reporting Requirements. For five years, the Company will furnish to the Representatives and, upon request, to each of the other Underwriters, as soon as practicable after the end of each fiscal year, a copy of its annual report to stockholders for such year; and the Company will furnish to the Representatives (i) as soon as available, a copy of each report and any definitive proxy statement of the Company filed with the Commission under the Exchange Act or mailed to stockholders, and (ii) from time to time, such other information concerning the Company as the Representatives may reasonably request. However, so long as the Company is subject to the reporting requirements of either Section 13 or Section 15(d) of the Exchange Act and is timely filing reports with the Commission on its Electronic Data Gathering, Analysis and Retrieval system (“EDGAR”), it is not required to furnish such reports or statements to the Underwriters.

     (h) Payment of Expenses. The Company agrees with the several Underwriters that the Company will pay all expenses incident to the performance of the obligations of the Company and the Selling Stockholder under this Agreement, including but not limited to any filing fees and other expenses (including fees and disbursements of counsel to the Underwriters) incurred in connection with qualification of the Offered Securities for sale under the laws of such jurisdictions as the Representatives designate and the preparation and printing of memoranda relating thereto, costs and expenses related to the review by the Financial Industry Regulatory Authority of the Offered Securities (including filing fees), costs and expenses relating to investor presentations or any “road show” in connection with the offering and sale of the Offered Securities including, without limitation, any travel expenses of the Company’s officers and employees and any other expenses of the Company including the chartering of airplanes, fees and expenses incident to listing the Company Offered Securities on the New York Stock Exchange, American Stock Exchange, NASDAQ Global Stock Market and other national and foreign exchanges, fees and expenses in connection with the registration of the Offered Securities under the Exchange Act and expenses incurred in distributing preliminary prospectuses and the Final Prospectus (including any amendments and supplements thereto) to the Underwriters and for expenses incurred for preparing, printing and distributing any Issuer Free Writing Prospectuses to investors or prospective investors. The Selling Stockholder agrees with the several Underwriters that it will pay any transfer taxes on the sale of its Offered Securities to the Underwriters.

     (i) Use of Proceeds. The Company expects to use the net proceeds received by it in connection with this offering in the manner described in the “Use of Proceeds” section of the General Disclosure Package and, except as disclosed in the General Disclosure Package, the Company does not intend to use any of the proceeds from the sale of the Offered Securities hereunder to repay any outstanding debt owed to any affiliate of any Underwriter.

     (j) Absence of Manipulation. The Company and the Selling Stockholder will not take, directly or indirectly, any action designed to or that would constitute or that might reasonably be expected to cause or result in, stabilization or manipulation of the price of any securities of the Company to facilitate the sale or resale of the Offered Securities.

     (k) Restriction on Sale of Securities by Company. For the period specified below (the “Lock-Up Period”), the Company will not, directly or indirectly, take any of the following actions with respect to its Securities, the Offered Securities or any securities convertible into or exchangeable or exercisable for any of its Securities or Offered Securities (“Lock-Up Securities”): (i) offer, sell, issue, contract to sell, pledge or otherwise dispose of Lock-Up Securities, (ii) offer, sell, issue, contract to sell, contract to purchase or grant any option, right or warrant to purchase Lock-Up Securities, (iii) enter into any swap, hedge or any other agreement that transfers, in whole or in part, the economic consequences of ownership of Lock-Up Securities, (iv) establish or increase a put equivalent position or liquidate or decrease a call equivalent position in Lock-Up Securities within the meaning of Section 16 of the Exchange Act or (v) file with the Commission a registration statement under the Act relating to Lock-Up Securities, or publicly disclose the intention to take any such action, without the prior written consent of the Representatives, except (i) issuances of Lock-Up Securities upon the exercise of options disclosed as outstanding in the General Disclosure Package or described in subsection (ii) below, (ii) the grant by the Company of stock options, stock appreciation rights, restricted stock, restricted stock units or other stock-based awards pursuant to the Company’s 2009 Long-Term Incentive Plan as described in the General Disclosure Package, (iii) the issuance by the Company of Securities in an amount not to exceed 10% of the total number of shares of Offered Securities as consideration or partial consideration for the acquisition of another corporation or entity or the acquisition of assets or properties of any such corporation or entity, or in connection with a licensing, lending or similar transaction, or (iv) the filing of any registration statement on Form S-8 with respect to any stock incentive plan or stock ownership plan relating to securities described in clause (i) or (ii) above; provided, however, that in each case described in clause (iii) above, each of the recipients of the Securities agrees in writing to the Representatives to be bound by the restrictions described in this paragraph for the remainder of such Lock-Up Period. The initial Lock-Up Period will

commence on the date hereof and continue for 90 days after the date hereof or such earlier date that the Representatives consent to in writing; provided, however, that if (1) during the last 17 days of the initial Lock-Up Period, the Company releases earnings results or material news or a material event relating to the Company occurs or (2) prior to the expiration of the initial Lock-Up Period, the Company announces that it will release earnings results during the 16-day period beginning on the last day of the initial Lock-Up Period, then in each case the Lock-Up Period will be extended until the expiration of the 18-day period beginning on the date of release of the earnings results or the occurrence of the materials news or material event, as applicable, unless the Representatives waive, in writing, such extension. The Company will provide the Representatives with notice of any announcement described in clause (2) of the preceding sentence that gives rise to an extension of the Lock-Up Period.

     6. Free Writing Prospectuses. (a) Issuer Free Writing Prospectuses. The Company and the Selling Stockholder represent and agree that, unless they obtain the prior consent of the Representatives, and each Underwriter represents and agrees that, unless it obtains the prior consent of the Company and the Representatives, it has not made and will not make any offer relating to the Offered Securities that would constitute an Issuer Free Writing Prospectus, or that would otherwise constitute a “free writing prospectus,” as defined in Rule 405, required to be filed with the Commission. Any such free writing prospectus consented to by the Company and the Representatives is hereinafter referred to as a “Permitted Free Writing Prospectus.” The Company represents that it has treated and agrees that it will treat each Permitted Free Writing Prospectus as an “issuer free writing prospectus,” as defined in Rule 433, and has complied and will comply with the requirements of Rules 164 and 433 applicable to any Permitted Free Writing Prospectus, including timely Commission filing where required, legending and record keeping. The Company represents that is has satisfied and agrees that it will satisfy the conditions in Rule 433 to avoid a requirement to file with the Commission any electronic road show.

     7. Conditions of the Obligations of the Underwriters. The obligations of the several Underwriters to purchase and pay for the Firm Securities on the First Closing Date and the Optional Securities to be purchased on each Optional Closing Date will be subject to the accuracy of the representations and warranties of the Company and, in the case of the First Closing Date, the Selling Stockholder herein on the date hereof (and as though made on such Closing Date), to the accuracy of the statements of Company officers made pursuant to the provisions hereof, to the performance by the Company and the Selling Stockholder of their obligations hereunder and to the following additional conditions precedent:

     (a) Accountants’ Comfort Letter. The Representatives shall have received letters, dated, respectively, the date hereof and each Closing Date, of PricewaterhouseCoopers LLP confirming that they are each a registered public accounting firm and independent public accountants within the meaning of the Securities Laws and in form and substance reasonably satisfactory to the Representatives (except that, in any letter dated a Closing Date, the specified date referred to shall be a date no more than three days prior to such Closing Date).

     (b) Effectiveness of Registration Statement. If the Effective Time of the Additional Registration Statement (if any) is not prior to the execution and delivery of this Agreement, such Effective Time shall have occurred not later than 10:00 P.M., New York time, on the date of this Agreement or, if earlier, the time the Final Prospectus is finalized and distributed to any Underwriter, or shall have occurred at such later time as shall have been consented to by the Representatives. The Final Prospectus shall have been filed with the Commission in accordance with the Rules and Regulations and Section 5(a) hereof. Prior to such Closing Date, no stop order suspending the effectiveness of a Registration Statement shall have been issued and no proceedings for that purpose shall have been instituted or, to the knowledge of the Selling Stockholder, the Company or the Representatives, shall be contemplated by the Commission.

     (c) No Material Adverse Change. Subsequent to the execution and delivery of this Agreement, there shall not have occurred (i) any change, nor any development or event involving a prospective change, in the condition (financial or otherwise), results of operations, business or properties of the Company and its subsidiaries taken as a whole which, in the judgment of the Representatives, is material and adverse and makes it impractical or inadvisable to market the

Offered Securities; (ii) any downgrading in the rating of any debt securities or preferred stock of the Company by any “nationally recognized statistical rating organization” (as defined for purposes of Rule 436(g)), or any public announcement that any such organization has under surveillance or review its rating of any debt securities or preferred stock of the Company (other than an announcement with positive implications of a possible upgrading, and no implication of a possible downgrading, of such rating); (iii) any change in U.S. or international financial, political or economic conditions or currency exchange rates or exchange controls the effect of which is such as to make it, in the judgment of the Representatives, impractical to market or to enforce contracts for the sale of the Offered Securities, whether in the primary market or in respect of dealings in the secondary market; (iv) any suspension or material limitation of trading in securities generally on the New York Stock Exchange or any setting of minimum or maximum prices for trading on such exchange; (v) any suspension of trading of any securities of the Company on any exchange or in the over-the-counter market; (vi) any banking moratorium declared by any U.S. Federal or New York authorities; (vii) any major disruption of settlements of securities, payment or clearance services in the United States or any other country where such securities are listed or (viii) any attack on, outbreak or escalation of hostilities or act of terrorism involving the United States, any declaration of war by Congress or any other national or international calamity or emergency if, in the judgment of the Representatives, the effect of any such attack, outbreak, escalation, act, declaration, calamity or emergency is such as to make it impractical or inadvisable to market the Offered Securities or to enforce contracts for the sale of the Offered Securities.

     (d) Opinion of Counsel for the Company. The Representatives shall have received an opinion, dated such Closing Date, of Fulbright & Jaworski L.L.P., counsel for the Company, substantially in the form of Exhibit A hereto.

     (e) Opinion of In-house Counsel for the Company. The Representatives shall have received an opinion, dated such Closing Date, of Michael Keefe, Esq., general counsel for the Company, substantially in the form of Exhibit B hereto.

     (f) Opinion of Counsel for Selling Stockholder. The Representatives shall have received an opinion, dated such Closing Date, of Kirkland & Ellis LLP, counsel for the Selling Stockholder, substantially in the form of Exhibit C hereto.

     (g) Opinion of Counsel for Underwriters. The Representatives shall have received from Cravath, Swaine & Moore LLP, counsel for the Underwriters, such opinion or opinions, dated such Closing Date, with respect to such matters as the Representatives may require, and the Selling Stockholder and the Company shall have furnished to such counsel such documents as they request for the purpose of enabling them to pass upon such matters.

     (h) Officers’ Certificate. The Representatives shall have received a certificate, dated such Closing Date, of an executive officer of the Company and a principal financial or accounting officer of the Company in which such officers shall state that: the representations and warranties of the Company in this Agreement are true and correct; the Company has complied with all agreements and satisfied all conditions on its part to be performed or satisfied hereunder at or prior to such Closing Date; no stop order suspending the effectiveness of any Registration Statement has been issued and no proceedings for that purpose have been instituted or, to the best of their knowledge and after reasonable investigation, are contemplated by the Commission; the Additional Registration Statement (if any) satisfying the requirements of subparagraphs (1) and (3) of Rule 462(b) was timely filed pursuant to Rule 462(b), including payment of the applicable filing fee in accordance with Rule 111(a) or (b) of Regulation S-T of the Commission; and, subsequent to the date of the most recent financial statements in the General Disclosure Package, there has been no material adverse change in the condition (financial or otherwise), results of operations, business, properties or prospects of the Company and its subsidiaries taken as a whole except as set forth in the General Disclosure Package or as described in such certificate.

     (i) Lock-Up Agreements. On or prior to the date hereof, the Representatives shall have received lockup letters from (i) each of the executive officers and directors of the Company and (ii) the Selling Stockholder.

     (j) Tax Information for the Selling Stockholder. The Selling Stockholder will deliver to the Representatives a properly completed and executed United States Treasury Department Form W-9 (or other applicable form or statement specified by the United States Treasury Department regulations in lieu thereof).

The Selling Stockholder and the Company will furnish the Representatives with such conformed copies of such opinions, certificates, letters and documents as the Representatives reasonably request. The Representatives may waive on behalf of the Underwriters compliance with any conditions to the obligations of the Underwriters hereunder, whether in respect of an Optional Closing Date or otherwise.

     8. Indemnification and Contribution. (a) Indemnification of Underwriters by Company. The Company will indemnify and hold harmless each Underwriter, its partners, members, directors, officers, employees, agents, affiliates and each person, if any, who controls such Underwriter within the meaning of Section 15 of the Act or Section 20 of the Exchange Act (each an “Indemnified Party”), against any and all losses, claims, damages or liabilities, joint or several, to which such Indemnified Party may become subject, under the Act, the Exchange Act, other Federal or state statutory law or regulation or otherwise, insofar as such losses, claims, damages or liabilities (or actions in respect thereof) arise out of or are based upon any untrue statement or alleged untrue statement of any material fact contained in any part of any Registration Statement at any time, any Statutory Prospectus as of any time, the Final Prospectus or any Issuer Free Writing Prospectus, or arise out of or are based upon the omission or alleged omission of a material fact required to be stated therein or necessary to make the statements therein, in light of the circumstances under which they were made, not misleading, and will reimburse each Indemnified Party for any legal or other expenses reasonably incurred by such Indemnified Party in connection with investigating or defending against any loss, claim, damage, liability, action, litigation, investigation or proceeding whatsoever (whether or not such Indemnified Party is a party thereto), whether threatened or commenced, and in connection with the enforcement of this provision with respect to any of the above as such expenses are incurred; provided, however, that the Company will not be liable in any such case to the extent that any such loss, claim, damage or liability arises out of or is based upon an untrue statement or alleged untrue statement in or omission or alleged omission from any of such documents in reliance upon and in conformity with written information furnished to the Company by any Underwriter through the Representatives specifically for use therein, it being understood and agreed that the only such information furnished by any Underwriter consists of the information described as such in subsection (c) below.

     (b) Indemnification of Underwriters by the Selling Stockholder. The Selling Stockholder will indemnify and hold harmless each Indemnified Party against any and all losses, claims, damages or liabilities, joint or several, to which such Indemnified Party may become subject, under the Act, the Exchange Act, other Federal or state statutory law or regulation or otherwise, insofar as such losses, claims, damages or liabilities (or actions in respect thereof) arise out of or are based upon any untrue statement or alleged untrue statement of any material fact contained in any part of any Registration Statement at any time, any Statutory Prospectus as of any time, the Final Prospectus or any Issuer Free Writing Prospectus, or arise out of or are based upon the omission or alleged omission of a material fact required to be stated therein or necessary to make the statements therein, in light of the circumstances under which they were made, not misleading, in each case only to the extent that such untrue statements or alleged untrue statements in or omissions or alleged omissions from a Registration Statement or the Final Prospectus were made in reliance upon and in conformity with written information furnished to the Company by the Selling Stockholder specifically for use therein, it being understood and agreed that the only such information furnished by the Selling Stockholder is the Selling Stockholder Information and will reimburse each Indemnified Party for any legal or other expenses reasonably incurred by such Indemnified Party in connection with investigating or defending against any loss, claim, damage, liability, action, litigation, investigation or proceeding whatsoever (whether or not such Indemnified Party is a party thereto), whether threatened or commenced, in connection with the enforcement of this provision with respect to the above as such expenses are incurred; provided, however, that the Selling Stockholder will not be liable in any such

case to the extent that any such loss, claim, damage or liability arises out of or is based upon an untrue statement or alleged untrue statement in or omission or alleged omission from any of such documents in reliance upon and in conformity with written information furnished to the Company by any Underwriter through the Representatives specifically for use therein, it being understood and agreed that the only such information furnished by any Underwriter consists of the information described as such in subsection (c) below; provided further, however, that the liability under this subsection of the Selling Stockholder shall be limited to an amount equal to the aggregate gross proceeds after deducting underwriting commissions and discounts, but before deducting expenses, to the Selling Stockholder from the sale of the Firm Securities sold by the Selling Stockholder hereunder.

     (c) Indemnification of Company and Selling Stockholder. Each Underwriter will severally and not jointly indemnify and hold harmless the Company, each of its directors and each of its officers who signs a Registration Statement and each person, if any, who controls the Company within the meaning of Section 15 of the Act or Section 20 of the Exchange Act, and the Selling Stockholder (each, an “Underwriter Indemnified Party”) against any losses, claims, damages or liabilities to which such Underwriter Indemnified Party may become subject, under the Act, the Exchange Act, or other Federal or state statutory law or regulation or otherwise, insofar as such losses, claims, damages or liabilities (or actions in respect thereof) arise out of or are based upon any untrue statement or alleged untrue statement of any material fact contained in any Registration Statement at any time, any Statutory Prospectus at any time, the Final Prospectus or any Issuer Free Writing Prospectus or arise out of or are based upon the omission or the alleged omission of a material fact required to be stated therein or necessary to make the statements therein not misleading, in each case to the extent, but only to the extent, that such untrue statement or alleged untrue statement or omission or alleged omission was made in reliance upon and in conformity with written information furnished to the Company by such Underwriter through the Representatives specifically for use therein, and will reimburse any legal or other expenses reasonably incurred by such Underwriter Indemnified Party in connection with investigating or defending against any such loss, claim, damage, liability, action, litigation, investigation or proceeding whatsoever (whether or not such Underwriter Indemnified Party is a party thereto), whether threatened or commenced, based upon any such untrue statement or omission, or any such alleged untrue statement or omission as such expenses are incurred, it being understood and agreed that the only such information furnished by any Underwriter consists of the following information in the Final Prospectus appearing under the caption “Underwriting”: the concession and reallowance figures appearing in the third paragraph.

     (d) Actions against Parties; Notification. Promptly after receipt by an indemnified party under this Section of notice of the commencement of any action, such indemnified party will, if a claim in respect thereof is to be made against an indemnifying party under subsection (a), (b) or (c) above, notify the indemnifying party of the commencement thereof; but the failure to notify the indemnifying party shall not relieve it from any liability that it may have under subsection (a), (b) or (c) above except to the extent that it has been materially prejudiced (through the forfeiture of substantive rights or defenses) by such failure; and provided further that the failure to notify the indemnifying party shall not relieve it from any liability that it may have to an indemnified party otherwise than under subsection (a), (b) or (c) above. In case any such action is brought against any indemnified party and it notifies an indemnifying party of the commencement thereof, the indemnifying party will be entitled to participate therein and, to the extent that it may wish, jointly with any other indemnifying party similarly notified, to assume the defense thereof, with counsel satisfactory to such indemnified party (who shall not, except with the consent of the indemnified party, be counsel to the indemnifying party), and after notice from the indemnifying party to such indemnified party of its election so to assume the defense thereof, the indemnifying party will not be liable to such indemnified party under this Section for any legal or other expenses subsequently incurred by such indemnified party in connection with the defense thereof other than reasonable costs of investigation. No indemnifying party shall, without the prior written consent of the indemnified party, effect any settlement of any pending or threatened action in respect of which any indemnified party is or could have been a party and indemnity could have been sought hereunder by such indemnified party unless such settlement (i) includes an unconditional release of such indemnified party from all liability on any claims that are the subject matter of such action and (ii) does not include a statement as to, or an admission of, fault, culpability or a failure to act by or on behalf of an indemnified party.

     (e) Contribution. If the indemnification provided for in this Section is unavailable or insufficient to hold harmless an indemnified party under subsection (a), (b) or (c) above, then each indemnifying party shall contribute to the amount paid or payable by such indemnified party as a result of the losses, claims, damages or liabilities referred to in subsection (a), (b) or (c) above (i) in such proportion as is appropriate to reflect the relative benefits received by the Company and the Selling Stockholder on the one hand and the Underwriters on the other from the offering of the Securities or (ii) if the allocation provided by clause (i) above is not permitted by applicable law, in such proportion as is appropriate to reflect not only the relative benefits referred to in clause (i) above but also the relative fault of the Company and the Selling Stockholder on the one hand and the Underwriters on the other in connection with the statements or omissions which resulted in such losses, claims, damages or liabilities as well as any other relevant equitable considerations. The relative benefits received by the Company and the Selling Stockholder on the one hand and the Underwriters on the other shall be deemed to be in the same proportion as the total net proceeds from the offering (before deducting expenses) received by the Company and the Selling Stockholder bear to the total underwriting discounts and commissions received by the Underwriters. The relative fault shall be determined by reference to, among other things, whether the untrue or alleged untrue statement of a material fact or the omission or alleged omission to state a material fact relates to information supplied by the Company, the Selling Stockholder or the Underwriters and the parties’ relative intent, knowledge, access to information and opportunity to correct or prevent such untrue statement or omission. The amount paid by an indemnified party as a result of the losses, claims, damages or liabilities referred to in the first sentence of this subsection (e) shall be deemed to include any legal or other expenses reasonably incurred by such indemnified party in connection with investigating or defending any action or claim which is the subject of this subsection (e). Notwithstanding the provisions of this subsection (e), (i) no Underwriter shall be required to contribute any amount in excess of the amount by which the total price at which the Securities underwritten by it and distributed to the public were offered to the public exceeds the amount of any damages which such Underwriter has otherwise been required to pay by reason of such untrue or alleged untrue statement or omission or alleged omission and (ii) the liability under this subsection of the Selling Stockholder shall be limited to an amount equal to the aggregate gross proceeds after underwriting commissions and discounts, but before expenses, to the Selling Stockholder from the sale of Firm Securities sold by the Selling Stockholder hereunder. No person guilty of fraudulent misrepresentation (within the meaning of Section 11(f) of the Act) shall be entitled to contribution from any person who was not guilty of such fraudulent misrepresentation. The Underwriters’ obligations in this subsection (e) to contribute are several in proportion to their respective underwriting obligations and not joint. The Company, the Selling Stockholder and the Underwriters agree that it would not be just and equitable if contribution pursuant to this Section 8(e) were determined by pro rata allocation (even if the Underwriters were treated as one entity for such purpose) or by any other method of allocation which does not take account of the equitable considerations referred to in this Section 8(e).

     9. Default of Underwriters. If any Underwriter or Underwriters default in their obligations to purchase Offered Securities hereunder on either the First or any Optional Closing Date and the aggregate number of shares of Offered Securities that such defaulting Underwriter or Underwriters agreed but failed to purchase does not exceed 10% of the total number of shares of Offered Securities that the Underwriters are obligated to purchase on such Closing Date, the Representatives may make arrangements satisfactory to the Company and the Selling Stockholder for the purchase of such Offered Securities by other persons, including any of the Underwriters, but if no such arrangements are made by such Closing Date, the non-defaulting Underwriters shall be obligated severally, in proportion to their respective commitments hereunder, to purchase the Offered Securities that such defaulting Underwriters agreed but failed to purchase on such Closing Date. If any Underwriter or Underwriters so default and the aggregate number of shares of Offered Securities with respect to which such default or defaults occur exceeds 10% of the total number of shares of Offered Securities that the Underwriters are obligated to purchase on such Closing Date and arrangements satisfactory to the Representatives, the Company and the Selling Stockholder for the purchase of such Offered Securities by other persons are not made within 36 hours after such default, this Agreement will terminate without liability on the part of any non-defaulting Underwriter, the Company or the Selling Stockholder, except as provided in Section 10 (provided that if such default occurs with respect to Optional Securities after the First Closing Date, this Agreement will not terminate as to the Firm Securities or any Optional Securities purchased prior to such termination). As used in this Agreement, the

term “Underwriter” includes any person substituted for an Underwriter under this Section. Nothing herein will relieve a defaulting Underwriter from liability for its default.

     10. Survival of Certain Representations and Obligations. The respective indemnities, agreements, representations, warranties and other statements of the Selling Stockholder, of the Company or its officers and of the several Underwriters set forth in or made pursuant to this Agreement will remain in full force and effect, regardless of any investigation, or statement as to the results thereof, made by or on behalf of any Underwriter, the Selling Stockholder, the Company or any of their respective representatives, officers or directors or any controlling person, and will survive delivery of and payment for the Offered Securities. If the purchase of the Offered Securities by the Underwriters is not consummated for any reason other than solely because of the termination of this Agreement pursuant to Section 9 hereof, the Company will reimburse the Underwriters for all out-of-pocket expenses (including fees and disbursements of counsel) reasonably incurred by them in connection with the offering of the Offered Securities, and the respective obligations of the Company, the Selling Stockholder and the Underwriters pursuant to Section 8 hereof shall remain in effect. In addition, if any Offered Securities have been purchased hereunder, the representations and warranties in Section 2 and all obligations under Section 5 shall also remain in effect.

     11. Notices. All communications hereunder will be in writing and, if sent to the Underwriters, will be mailed, delivered or telegraphed and confirmed to the Representatives c/o J.P. Morgan Securities LLC, 383 Madison Avenue, New York, N.Y. 10179 (fax: (212)  ###-###-####), Attention: Equity Syndicate Desk and Merrill Lynch, Pierce, Fenner & Smith Incorporated, One Bryant Park, New York, N.Y. 10036 (fax: (646)  ###-###-####), Attention: Syndicate Department, with a copy to Merrill Lynch, Pierce, Fenner & Smith Incorporated, One Bryant Park, New York, N.Y. 10036 (fax: (212)  ###-###-####), Attention: ECM Legal; or, if sent to the Company, will be mailed, delivered or telegraphed and confirmed to it at 195 Clarksville Road, Princeton Junction, New Jersey 08550, Attention: Chief Executive Officer, with a copy to Fulbright & Jaworski L.L.P., 666 Fifth Avenue, New York, N.Y. 10103, Attention: Sheldon G. Nussbaum; or, if sent to the Selling Stockholder will be mailed, delivered or telegraphed and confirmed to Daniel M. Dickinson at TC NDT Holdings, L.L.C., 1445 Pennsylvania Avenue, N.W., Washington, D.C. 20004, with a copy to Kirkland & Ellis LLP, 300 North LaSalle, Chicago, IL 60654, Attention: Christopher Bennett; provided, however, that any notice to an Underwriter pursuant to Section 8 will be mailed, delivered or telegraphed and confirmed to such Underwriter.

     12. Successors. This Agreement will inure to the benefit of and be binding upon the parties hereto and their respective personal representatives and successors and the officers and directors and controlling persons referred to in Section 8, and no other person will have any right or obligation hereunder.

     13. Representation. The Representatives will act for the several Underwriters in connection with the transactions contemplated by this Agreement, and any action under this Agreement taken by the Representatives jointly will be binding upon all the Underwriters.

     14. Counterparts. This Agreement may be executed in any number of counterparts, each of which shall be deemed to be an original, but all such counterparts shall together constitute one and the same Agreement.

     15. Absence of Fiduciary Relationship. The Company and the Selling Stockholder severally acknowledge and agree that:

     (a) No Other Relationship. The Representatives have been retained solely to act as underwriters in connection with the sale of the Offered Securities and that no fiduciary, advisory or agency relationship between the Company or the Selling Stockholder, on the one hand, and the Representatives, on the other, has been created in respect of any of the transactions contemplated by this Agreement or the Final Prospectus, irrespective of whether the Representatives have advised or are advising the Company or the Selling Stockholder on other matters;

     (b) Arms’ Length Negotiations. The price of the Offered Securities set forth in this Agreement was established by Company and the Selling Stockholder following discussions and arms-length negotiations with the Representatives and the Company and the Selling Stockholder is capable of

evaluating and understanding and understand and accept the terms, risks and conditions of the transactions contemplated by this Agreement;

     (c) Absence of Obligation to Disclose. The Company and the Selling Stockholder have been advised that the Representatives and their affiliates are engaged in a broad range of transactions which may involve interests that differ from those of the Company or the Selling Stockholder and that the Representatives have no obligation to disclose such interests and transactions to the Company or the Selling Stockholder by virtue of any fiduciary, advisory or agency relationship; and

     (d) Waiver. The Company and the Selling Stockholder waive, to the fullest extent permitted by law, any claims they may have against the Representatives for breach of fiduciary duty or alleged breach of fiduciary duty and agree that the Representatives shall have no liability (whether direct or indirect) to the Company or the Selling Stockholder in respect of such a fiduciary duty claim or to any person asserting a fiduciary duty claim on behalf of or in right of the Company, including stockholders, employees or creditors of the Company.

     16. Applicable Law. This Agreement shall be governed by, and construed in accordance with, the laws of the State of New York.

     The Company hereby submits to the non-exclusive jurisdiction of the Federal and state courts in the Borough of Manhattan in The City of New York in any suit or proceeding arising out of or relating to this Agreement or the transactions contemplated hereby. The Company irrevocably and unconditionally waives any objection to the laying of venue of any suit or proceeding arising out of or relating to this Agreement or the transactions contemplated hereby in Federal and state courts in the Borough of Manhattan in the City of New York and irrevocably and unconditionally waives and agrees not to plead or claim in any such court that any such suit or proceeding in any such court has been brought in an inconvenient forum.

     If the foregoing is in accordance with the Representatives’ understanding of our agreement, kindly sign and return to the Company one of the counterparts hereof, whereupon it will become a binding agreement among the Selling Stockholder, the Company and the several Underwriters in accordance with its terms.

[Underwriting Agreement]

[Underwriting Agreement]

[Underwriting Agreement]

SCHEDULE A

		Number of
		Firm Securities
Underwriter		to be Purchased
J.P. Morgan Securities LLC			1,468,981
Merrill Lynch, Pierce, Fenner & Smith Incorporated			979,320
Robert W. Baird & Co. Incorporated			359,084
Stephens, Inc.			293,796
KeyBanc Capital Markets Inc.			163,220
Total			3,264,401

SCHEDULE B

		Number of
		Firm Securities
Selling Stockholder		to be Sold
TC NDT Holdings, L.L.C.			2,764,401
Total			2,764,401

SCHEDULE C

1.

Other Information Included in the General Disclosure Package

          The following information is also included in the General Disclosure Package:

1.

The initial price to the public of the Offered Securities: $16.00

SCHEDULE D

List of Significant Subsidiaries, as defined under Rule 1-02(w) of Regulation S-X

None

EXHIBIT A

FORM OF OPINION OF
FULBRIGHT & JAWORSKI L.L.P.

EXHIBIT B

FORM OF OPINION OF
GENERAL COUNSEL

EXHIBIT C

FORM OF OPINION OF
KIRKLAND & ELLIS LLP