COMMERCIAL GUARANTY

Exhibit 10.6

COMMERCIAL GUARANTY

AMOUNT OF GUARANTY. The amount of this Guaranty is Unlimited.

CONTINUING UNLIMITED GUARANTY. For good and valuable consideration, American Electric Technologies. Inc. (“Guarantor’) absolutely and unconditionally guarantees and promises to pay to JPMorgan Chase Bank, NA (“Lender”) or its order, in legal tender of the United States of America, the Indebtedness (as that term is defined below) of M & I Electric Industries, Inc. (“Borrower”) to Lender on the terms and conditions set forth in this Guaranty. Under this Guaranty, the liability of Guarantor is unlimited and the obligations of Guarantor are continuing.

INDEBTEDNESS GUARANTEED. The Indebtedness guaranteed by this Guaranty includes any and all of Borrower’s indebtedness to Lender and is used in the most comprehensive sense and means and includes any and all of Borrower’s liabilities, obligations and debts to Lender, now existing of hereinafter incurred or created, including, without limitation, all loans, advances, interest, costs, debts, overdraft indebtedness, credit card indebtedness, lease obligations, other obligations, and liabilities of Borrower, or any of them, and any present or future judgments against Borrower, or any of them; and whether any such Indebtedness is voluntarily or involuntarily incurred, due or not due, absolute or contingent, liquidated or unliquidated, determined or undetermined; whether Borrower may be liable individually or jointly with others, or primarily or secondarily, or as guarantor or surety; whether recovery on the Indebtedness may be or may become barred or unenforceable against Borrower for any reason whatsoever; and whether the Indebtedness arises from transactions which may be voidable on account of infancy, insanity, ultra vires, or otherwise.

NATURE OF GUARANTY. This Guaranty is a guaranty of payment and not of collection. Therefore, the Lender can insist that the Guarantor pay immediately, and the Lender is not required to attempt to collect first from the Borrower, any collateral, or any other person liable for the Indebtedness.

OTHER GUARANTIES. If Lender presently holds one or more guaranties, or hereafter receives additional guaranties from Guarantor, the rights of Lender under all guaranties shall be cumulative. This Guaranty shall not (unless specifically provided below to the contrary) affect or invalidate any such other guaranties. The liability of Guarantor will be the aggregate liability of Guarantor under the terms of this Guaranty and any such other unterminated guaranties.

DURATION OF GUARANTY. This Guaranty will take effect when received by Lender without the necessity of any acceptance by Lender, or any notice to Guarantor or to Borrower, and will continue in full force until all Indebtedness incurred or contracted before receipt by Lender of any notice of revocation shall have been fully and finally paid and satisfied and all of Guarantor’s other obligations under this Guaranty shall have been performed in full. If Guarantor elects to revoke this Guaranty, Guarantor may only do so in writing. Guarantor’s written notice of revocation must be mailed to Lender, by certified mail, at Lender’s address listed above or such other place as Lender may designate in writing. Written revocation of this Guaranty will apply only to advances or new Indebtedness created after actual receipt by Lender of Guarantor’s written revocation. For this purpose and without limitation, the term “new Indebtedness” does not include Indebtedness which at the time of notice of revocation is contingent, unliquidated, undetermined or not due and which later becomes absolute, liquidated, determined or due. This Guaranty will continue to bind Guarantor for all Indebtedness incurred by Borrower or committed by Lender prior to receipt of Guarantor’s written notice of revocation, including any extensions, renewals, substitutions or modifications of the Indebtedness. All renewals, extensions, substitutions, and modifications of the Indebtedness granted after Guarantor’s revocation, are contemplated under this Guaranty and, specifically will not be considered to be new Indebtedness. This Guaranty shall bind Guarantor’s estate as to Indebtedness created both before and after Guarantor’s death or incapacity, regardless of Lender’s actual notice of Guarantor’s death. Subject to the foregoing. Guarantor’s executor or administrator or other legal representative may terminate this Guaranty in the same manner in which Guarantor might have terminated it and with the same effect. Release of any other guarantor or termination of any other guaranty of the Indebtedness shall not affect the liability of Guarantor under this Guaranty. A revocation Lender receives from any one or more Guarantors shall not affect the liability of any remaining Guarantors under this Guaranty. Guarantor shall be liable, jointly and severally, with Borrower and any other guarantor of all or any part of the Indebtedness, and release of any other guarantor of all or any part of the Indebtedness, or termination or revocation of any other guaranty of all or any part of the Indebtedness, shall not affect the liability of Guarantor under this Guaranty. It is anticipated that fluctuations may occur in the aggregate amount of Indebtedness covered by this Guaranty, and Guarantor specifically acknowledges and agrees that reductions in the amount of Indebtedness, even to zero dollars ($0.00), prior to Guarantor’s written revocation of this Guaranty shall not constitute a termination of this Guaranty. This Guaranty is binding upon Guarantor and Guarantor’s heirs, successors and assigns so long as any of the guaranteed Indebtedness remains unpaid and even though the Indebtedness guaranteed may from time to time be zero dollars ($0.00).

GUARANTOR’S AUTHORIZATION TO LENDER. Guarantor authorizes Lender, either before or after any revocation hereof, without notice or demand and without lessening Guarantor’s liability under this Guaranty, from time to time: (A) prior to revocation as set forth above, to make one or more additional secured or unsecured loans to Borrower, to lease equipment or other goods to Borrower, or otherwise to extend additional credit to Borrower; (B) to alter, compromise, renew, extend, accelerate, or otherwise change one or more times the time for payment or other terms of the Indebtedness or any part of the Indebtedness, including increases and decreases of the rate of interest on the Indebtedness; extensions may be repeated and may be for longer than the original loan term; (C) to take and hold security for the payment of this Guaranty or the Indebtedness, and exchange, enforce, waive, subordinate, fail or decide not to perfect, and release any such security, with or without the substitution of new collateral, and release the Borrower, with or without the assumption of the Indebtedness by any other entity; (D) to release, substitute, agree not to sue, or deal with any one or more of Borrower’s sureties, endorsers, or other guarantors on any terms or in any manner Lender may choose; (E) to determine how, when and what application of payments and credits shall be made on the Indebtedness (F) to apply such security and direct the order or manner of sale thereof, including without limitation, any nonjudicial sale permitted by the terms of the controlling security agreement or deed of trust, as Lender in its discretion may determine; (G) to sell, transfer, assign or grant participations in all or any part of the Indebtedness; and (H) to assign or transfer this Guaranty in whole or in part.

GUARANTOR’S REPRESENTATIONS AND WARRANTIES. Guarantor represents and warrants to Lender that (A) no representations or agreements of any kind have been made to Guarantor which would limit or qualify in any way the terms of this Guaranty: (B) this Guaranty is executed at Borrower’s request and not at the request of Lender, (C) Guarantor has full power, right and authority to enter into this Guaranty; (D) the provisions of this Guaranty do not conflict with or result in a default under any agreement or other instrument binding upon Guarantor and do not result in a violation of any law, regulation, court decree or order applicable to Guarantor; (E) Guarantor has not and will not, without the prior written consent of Lender, sell, lease, assign, encumber, hypothecate, transfer, or otherwise dispose of all or substantially all of Guarantor’s assets, or any interest therein; (F) upon Lender’s request. Guarantor will provide to Lender financial and credit information in form acceptable to Lender, and all such financial information which currently has been, and all future financial information which will be provided to Lender is and will be true and correct in all material respects and fairly present Guarantor’s financial condition as of the dates the financial information is provided; (G) no material adverse change has occurred in Guarantor’s financial condition since the date of the most recent financial statements provided to Lender and no event has occurred which may materially adversely affect Guarantor’s financial condition; (H) no litigation, claim, investigation, administrative proceeding or similar action (including those for unpaid taxes) against Guarantor is pending or threatened; (I) Lender has made no representation to Guarantor as to the creditworthiness of Borrower; (J) Guarantor has established adequate means of obtaining from Borrower on a continuing basis information regarding Borrower’s financial condition; and (K) as of the date hereof, and after giving effect to this Guaranty, (1) Guarantor is and will be solvent, (2) the fair saleable value of Guarantor’s assets exceeds and will continue to exceed Guarantor’s liabilities (both fixed and contingent). (3) Guarantor is and will continue to be able to pay Guarantor’s debts as they mature, and (4) if Guarantor is not an individual, Guarantor has and will continue to have sufficient capital to carry on its business and all businesses in which it is about to engage. Guarantor agrees to keep adequately informed from such means of any facts, events, or circumstances which might in any way affect Guarantor’s risks under this Guaranty, and Guarantor further agrees that Lender shall have no obligation to disclose to Guarantor any information or documents acquired by Lender in the course of its relationship with Borrower.

GUARANTOR’S FINANCIAL STATEMENTS. Guarantor agrees to furnish Lender with the following:

Annual Statements. As soon as available, but in no event later than 150 days after the end of each fiscal year, Guarantor’s balance sheet and income statement for the year ended, audited by a certified public accountant satisfactory to Lender.

All financial reports required to be provided under this Guaranty shall be prepared in accordance with GAAP, applied on a consistent basis, and certified by Guarantor as being true and correct.

GUARANTOR’S WAIVERS. Except as prohibited by applicable law, Guarantor waives any right to require Lender (A) to continue lending money or to extend other credit to Borrower; (B) to make any presentment, protest, demand, or notice of any kind, including notice of any nonpayment of the Indebtedness or of any nonpayment related to any collateral, or notice of any action or nonaction on the part of Borrower, Lender, any surety, endorser, or other guarantor in connection with the Indebtedness or in connection with the creation of new or additional loans or obligations; (C) to resort for payment or to proceed directly or at once against any person, including Borrower or any other guarantor;

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(D) to proceed directly against or exhaust any collateral held by Lender from Borrower, any other guarantor, or any other person; (E) (Fl to pursue any other remedy within Lender’s power; or (G) to commit any act or omission of any kind, or at any time, with respect to any matter whatsoever.

In addition to the waivers set forth herein, if now or hereafter Borrower is or shall become insolvent and the Indebtedness shall not at all times until paid be fully secured by collateral pledged by Borrower, Guarantor hereby forever waives and gives up in favor of Lender and Borrower, and Lender’s and Borrower’s respective successors, any claim or right to payment Guarantor may now have or hereafter have or acquire against Borrower, by subrogation or otherwise, so that at no time shall Guarantor be or become a “creditor” of Borrower within the meaning of 11 U.S.C. section 547(b), or any successor provision of the Federal bankruptcy laws.

The Guarantor agrees that the provisions of this Guaranty are severable, and in any action or proceeding involving any state corporate law. or any state, federal or foreign bankruptcy, insolvency, reorganization or other law affecting the rights of creditors generally, if the obligations of the Guarantor under this Guaranty would otherwise be held or determined to be avoidable, invalid or unenforceable on account of the amount of the Guarantor’s liability under this Guaranty, then, notwithstanding any other provision of this Guaranty to the contrary, the amount of such liability shall, without any further action by the Guarantor or the Lender, be automatically limited and reduced to the highest amount that is valid and enforceable as determined in such action or proceeding.

Guarantor also waives any and all rights or defenses arising by reason of IA) any “one action” or “anti-deficiency” law or any other law which may prevent Lender from bringing any action, including a claim for deficiency, against Guarantor, before or after Lender’s commencement or completion of any foreclosure action, either judicially or by exercise of a power of sale; (B) any election of remedies by Lender which destroys or otherwise adversely affects Guarantor’s subrogation rights or Guarantor’s rights to proceed against Borrower for reimbursement, including without limitation, any loss of rights Guarantor may suffer by reason of any law limiting, qualifying, or discharging the Indebtedness; (C) any disability or other defense of Borrower, of any other guarantor, or of any other person, or by reason of the cessation of Borrower’s liability from any cause whatsoever, other than payment in full in legal tender, of the Indebtedness; (D) any right to claim discharge of the Indebtedness on the basis of unjustified impairment of any collateral for the Indebtedness; (E) any statute of limitations, if at any time any action or suit brought by Lender against Guarantor is commenced there is outstanding Indebtedness of Borrower to Lender which is not barred by any applicable statute of limitations; (F) any right to claim the Guaranty is conditioned on anyone else executing this or any other guaranty; or (G) any defenses given to guarantors at law or in equity other than actual payment and performance of the Indebtedness. If payment is made by Borrower, whether voluntarily or otherwise, or by any third party, on the Indebtedness and thereafter Lender is forced to remit the amount of that payment to Borrower’s trustee in bankruptcy or to any similar person under any federal or state bankruptcy law or law for the relief of debtors, the Indebtedness shall be considered unpaid for the purpose of the enforcement of this Guaranty.

Guarantor further waives and agrees not to assert or claim at any time any deductions to the amount guaranteed under this Guaranty for any claim Of setoff, counterclaim, counter demand, recoupment or similar right, whether such claim, demand or right may be asserted by the Borrower, the Guarantor, or both.

GUARANTOR’S UNDERSTANDING WITH RESPECT TO WAIVERS. Guarantor warrants and agrees that each of the waivers set forth above is made with Guarantor’s full knowledge of its significance and consequences and that, under the circumstances, the waivers are reasonable and not contrary to public policy or law. If any such waiver is determined to be contrary to any applicable law or public policy, such waiver shall be effective only to the extent permitted by law or public policy.

RIGHT OF SETOFF. Guarantor grants to Lender a security interest in, as well as a right of setoff against, and hereby assigns, conveys, delivers, pledges and transfers to Lender, as security for repayment of the Indebtedness, all Guarantor’s right, title and interest in and to all Guarantor’s accounts (whether checking, savings, or some other account) with Lender or any subsidiary or affiliate of JPMorgan Chase & Co. (each hereinafter referred to as a “Lender Affiliate”) and all other obligations at any time owing by Lender or any Lender Affiliate to Guarantor. This includes all accounts Guarantor holds jointly with someone else and all accounts Guarantor may open in the future. However, this does not include any IRA or Keogh accounts, or any trust accounts for which the grant of a security interest would be prohibited by law. Guarantor authorizes Lender, without prior notice to Guarantor and irrespective of (i) whether or not Lender has made any demand under this Guaranty or the Related Documents or (ii) whether such Indebtedness is contingent, matured or unmatured, to the extent permitted by law, to collect, charge and/or setoff all sums owing on the Indebtedness against any and all such accounts and other obligations, and, at Lender’s option, to administratively freeze or direct a Lender Affiliate to administratively freeze alt such accounts and other obligations to allow Lender to protect Lender’s security interest, collection, charge and setoff rights provided in this paragraph.

SUBORDINATION OF BORROWER’S DEBTS TO GUARANTOR. Guarantor agrees that the Indebtedness of Borrower to Lender, whether now existing or hereafter created, shall be superior to any claim that Guarantor may now have or hereafter acquire against Borrower, whether or not Borrower becomes insolvent. Guarantor hereby expressly subordinates any claim Guarantor may have against Borrower, upon any account whatsoever, to any claim that Lender may now or hereafter have against Borrower. In the event of insolvency and consequent liquidation of the assets of Borrower, through bankruptcy, by an assignment for the benefit of creditors, by voluntary liquidation, or otherwise, the assets of Borrower applicable to the payment of the claims of both Lender and Guarantor shall be paid to Lender and shall be first applied by Lender to the Indebtedness of Borrower to Lender. Guarantor does hereby assign to Lender all claims which it may have or acquire against Borrower or against any assignee or trustee in bankruptcy of Borrower; provided however, that such assignment shall be effective only for the purpose of assuring to Lender full payment in legal tender of the Indebtedness. If Lender so requests, any notes or credit agreements now or hereafter evidencing any debts or obligations of Borrower to Guarantor shall be marked with a legend that the same are subject to this Guaranty and shall be delivered to Lender. Guarantor agrees, and Lender is hereby authorized, in the name of Guarantor, from time to time to file financing statements and continuation statements and to execute documents and to take such other actions as Lender deems necessary or appropriate to perfect, preserve and enforce its rights under this Guaranty.

MISCELLANEOUS PROVISIONS. The following miscellaneous provisions are a part of this Guaranty:

Amendments. This Guaranty, together with any Related Documents, constitutes the entire understanding and agreement of the parties as to the matters set forth in this Guaranty. No alteration of or amendment to this Guaranty shall be effective unless given in writing and signed by the party or parties sought to be charged or bound by the alteration or amendment.

Attorneys’ Fees; Expenses. Guarantor agrees to pay upon demand all of Lender’s costs and expenses, including Lender’s Lender’s reasonable attorneys’ fees and Lender’s legal expenses, incurred in connection with the enforcement of this Guaranty. Lender may hire or pay someone else to help enforce this Guaranty, and Guarantor shall pay the costs and expenses of such enforcement. Costs and expenses include Lender’s Lender’s reasonable attorneys’ tees and legal expenses whether or not there is a lawsuit, including Lender’s reasonable attorneys’ fees and legal expenses for bankruptcy proceedings (including efforts to modify or vacate any automatic stay or injunction), appeals, and any anticipated post-judgment collection services. Guarantor also shall pay all court costs and such additional fees as may be directed by the court.

Caption Headings. Caption headings in this Guaranty are for convenience purposes only and are not to be used to interpret or define the provisions of this Guaranty.

Integration. Guarantor further agrees that Guarantor has read and fully understands the terms of this Guaranty; Guarantor has had the opportunity to be advised by Guarantor’s attorney with respect to this Guaranty; the Guaranty fully reflects Guarantor’s intentions and parol evidence is not required to interpret the terms of this Guaranty. Guarantor hereby indemnifies and holds Lender harmless from all losses, claims, damages, and costs (including Lender’s attorneys’ fees! suffered or incurred by Lender as a result of any breach by Guarantor of the warranties, representations and agreements of this paragraph.

Interpretation. In all cases where there is more than one Borrower or Guarantor, then all words used in this Guaranty in the singular shall be deemed to have been used in the plural where the context and construction so require; and where there is more than one Borrower named in this Guaranty or when this Guaranty is executed by more than one Guarantor, the words “Borrower” and “Guarantor” respectively shall mean all and any one or more of them. The words “Guarantor,” “Borrower,” and “Lender” include the heirs, successors, assigns, and transferees of each of them. If a court finds that any provision of this Guaranty is not valid or should not be enforced, that fact by itself will not mean that the rest of this Guaranty will not be valid or enforced. Therefore, a court will enforce the rest of the provisions of this Guaranty even if a provision of this Guaranty may be found to be invalid or unenforceable. If any one or more of Borrower or Guarantor are corporations, partnerships, limited liability companies, or similar entities, it is not necessary for Lender to inquire into the powers of Borrower or Guarantor or of the officers, directors, partners, managers, or other agents acting or purporting to act on their behalf, and any Loan indebtedness made or created in reliance upon the professed exercise of such powers shall be guaranteed under this Guaranty.

Notices. Any notice required to be given under this Guaranty shall be given in writing, and, except for revocation notices by Guarantor, shall be effective when actually delivered, when actually received by telefacsimile [unless otherwise required by law), when deposited with a nationally recognized overnight courier, or, if mailed, when deposited in the United States mail, as first class, certified or registered mail postage prepaid, directed to the addresses shown near the beginning of this Guaranty. All revocation notices by Guarantor shall be in writing and shall be effective upon delivery to Lender as provided in the section of this Guaranty entitled “DURATION OF GUARANTY,” Any party may change its address for notices under this Guaranty by giving written notice to the other parties, specifying that the purpose of the notice is to change the party’s address. For notice purposes, Guarantor agrees to keep Lender informed at all times of Guarantor’s COMMERCIAL GUARANTY current address. Unless otherwise provided or required by law. if there is more than one Guarantor, any notice given by Lender to any Guarantor is deemed to be notice given to all Guarantors.

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No Waiver by Lender. Lender shall not be deemed to have waived any rights under this Guaranty unless such waiver is given in writing and signed by Lender. No delay or omission on the part of Lender in exercising any right shall operate as a waiver of such right or any other right. A waiver by Lender of a provision of this Guaranty shall not prejudice or constitute a waiver of Lender’s right otherwise to demand strict compliance with that provision or any other provision of this Guaranty. No prior waiver by Lender, nor any course of dealing between Lender and Guarantor, shall constitute a waiver of any of Lender’s rights or of any of Guarantor’s obligations as to any future transactions. Whenever the consent of Lender is required under this Guaranty, the granting of such consent by Lender in any instance shall not constitute continuing consent to subsequent instances where such consent is required and in all cases such consent may be granted or withheld in the sole discretion of Lender.

Successors and Assigns. Subject to any limitations stated in this Guaranty on transfer of Guarantor’s interest, this Guaranty shall be binding upon and inure to the benefit of the parties, their successors and assigns.

JURY WAIVER. THE UNDERSIGNED AND LENDER (BY ITS ACCEPTANCE HEREOF) HEREBY VOLUNTARILY, KNOWINGLY, IRREVOCABLY AND UNCONDITIONALLY WAIVE ANY RIGHT TO HAVE A JURY PARTICIPATE IN RESOLVING ANY DISPUTE (WHETHER BASED UPON CONTRACT, TORT OR OTHERWISE) BETWEEN OR AMONG THE UNDERSIGNED AND LENDER ARISING OUT OF OR IN ANY WAY RELATED TO THIS DOCUMENT, THE RELATED DOCUMENTS, OR ANY RELATIONSHIP BETWEEN OR AMONG THE UNDERSIGNED AND LENDER. THIS PROVISION IS A MATERIAL INDUCEMENT TO LENDER TO PROVIDE THE FINANCING EVIDENCED BY THIS DOCUMENT AND THE RELATED DOCUMENTS.

GOVERNING LAW. The Lender’s loan production office for this transaction is located at the address and in the State (the “LPO State”) indicated in the LPO address or the loan production office address on the first page of this document. This document will be governed by and interpreted in accordance with federal law and the laws of the LPO State, except for matters related to interest and the exportation of interest, which matters shall be governed by and interpreted in accordance with federal law (including, but not limited to, statutes, regulations, interpretations and opinions) and the laws of the State of Ohio. However, if there is ever a question about whether any provision of this document is valid or enforceable, the provision that is questioned will be governed by whichever state or federal law would find the provision to be valid and enforceable. The loan transaction which is evidenced by this document has been made in the State of Ohio.

VENUE. If there is a lawsuit, the undersigned agrees to submit to the jurisdiction of the courts of the county in the LPO State in which the Lender’s loan production office is located.

INFORMATION WAIVER. Lender may provide, without any limitation whatsoever, to any one or more purchasers of any Indebtedness, potential purchasers of any Indebtedness, or affiliates of JPMorgan Chase & Co., any information or knowledge Lender may have about Guarantor or about any matter relating to the Indebtedness, and Guarantor hereby waives any right to privacy Guarantor may have with respect to such matters.

EXAMPLES OF INDEBTEDNESS, INCLUDING DEPOSIT ACCOUNT INDEBTEDNESS, LOAN INDEBTEDNESS, ETC., TOGETHER WITH EXCLUSION OF BORROWER’S CONSUMER INDEBTEDNESS. Guarantor agrees the Indebtedness as described herein in the paragraph captioned “Indebtedness Guaranteed” is used in its most comprehensive sense. As examples, and not as limitation, the Indebtedness of Borrower includes: (a) any overdraft in any deposit account of Borrower, accruing for any reason, (b) any obligations, including any overdraft in any deposit account of Borrower, related to Automated Clearing House (“ACH”) services or products, deposit account services or products, or treasury management services or products, including any agreement with respect thereto; (c) any transaction (including any agreement with respect thereto) between Borrower and the Lender or JPMorgan Chase & Co., or any of its subsidiaries or affiliates or their successors, which is a rate swap, basis swap, forward rate transaction, commodity swap, commodity option, equity or equity index swap, equity or equity index option, bond option, interest rate option, foreign exchange transaction, cap transaction, floor transaction, collar transaction, forward transaction, currency swap transaction, cross-currency rate swap transaction, currency option or any other similar transaction (including any option with respect to any of these transactions) or any combination thereof, whether linked to one or more interest rates, foreign currencies, commodity prices, equity prices or other financial measures (each a “Rate Management Transaction”); (d) any obligation related to any loan or credit transaction (including any agreement with respect thereto), whether evidenced by a promissory note, credit agreement, letter of credit application, or any other agreement; (e) any obligation related to commercial credit card transactions (including an agreement with respect thereto); (f) any obligation related to any lease (including an agreement with respect thereto); (g) any obligation related to any guaranty of the obligations of others by Borrower: (h) any obligation under a Related Document; and (i) all other obligations of Borrower to Lender. The Indebtedness shall not include credit, obligations, liabilities, or indebtedness of the Borrower incurred primarily for personal, family or household purposes.

DEFINITIONS. The following capitalized words and terms shall have the following meanings when used in this Guaranty. Unless specifically stated to the contrary, all references to dollar amounts shall mean amounts in lawful money of the United States of America. Words and terms used in the singular shall include the plural, and the plural shall include the singular, as the context may require. Words and terms not otherwise defined in this Guaranty shall have the meanings attributed to such terms in the Uniform Commercial Code:

Borrower. The word “Borrower” means M & I Electric Industries, Inc. , and all other persons and entities signing the Note in whatever capacity.

GAAP. The word “GAAP” means generally accepted accounting principles.

Guarantor. The word “Guarantor” means each and every person or entity signing this Guaranty, including without limitation American Electric Technologies, Inc.

Guaranty. The word “Guaranty” means this guaranty from Guarantor to Lender.

Indebtedness. The word “Indebtedness” means Borrower’s indebtedness to Lender as more particularly described in this Guaranty.

Lender, The word “Lender” means JPMorgan Chase Bank, NA, its successors and assigns.

Related Documents. The words “Related Documents” mean all promissory notes, credit agreements, loan agreements, environmental agreements, guaranties, security agreements, mortgages, deeds of trust, security deeds, collateral mortgages, and all other instruments, agreements and documents, whether now existing or hereafter arising, executed in connection with the Indebtedness.

GUARANTOR ACKNOWLEDGES HAVING READ ALL THE PROVISIONS OF THIS COMMERCIAL GUARANTY AND GUARANTOR AGREES TO ITS TERMS. THIS COMMERCIAL GUARANTY IS DATED JULY 2, 2007.

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