AMENDMENT NO. 2 TO SHAREHOLDER RIGHTS AGREEMENT

Exhibit 4.2

AMENDMENT NO. 2

TO

SHAREHOLDER RIGHTS AGREEMENT

This Amendment No. 2 (the “Amendment”) to the Rights Agreement (as defined below) is entered into as of April 24, 2008, by and between ZOLL Medical Corporation, a Massachusetts corporation (the “Company”), and Computershare Trust Company, N.A. (as successor rights agent to State Street Bank and Trust Company), as Rights Agent (“Computershare”).

WITNESSETH:

WHEREAS, the Company is party to that certain Shareholder Rights Agreement, dated as of June 8, 1998, as amended (the “Rights Agreement”) with Computershare (as successor rights agent to State Street Bank and Trust Company), as Rights Agent. All capitalized terms used herein and not otherwise defined shall having the meaning ascribed to them in the Rights Agreement;

WHEREAS, pursuant to Section 27 of the Rights Agreement, the Company may prior to a Section 11(a)(ii) Event supplement or amend the Rights Agreement without the approval of any holders of certificates representing shares of common stock of the Company; and

WHEREAS, the Company now desires to amend the Rights Agreement as set forth in this Amendment, and pursuant to Section 27 of the Rights Agreement, the Company hereby directs that the Rights Agreement should be amended as set forth in this Amendment.

NOW THEREFORE, in consideration of the premises and the mutual agreements herein set forth, the parties hereby agree as follows:

1. Amendment to Section 7(a). The first sentence of Section 7(a) of the Rights Agreement is hereby amended to read as follows:

“(a) Subject to Section 7(e) hereof, the registered holder of any Right Certificate may exercise the Rights evidenced thereby (except as otherwise provided herein) in whole or in part at any time after the Distribution Date upon surrender of the Right Certificate, with the form of election to purchase on the reverse side thereof duly executed, to the Rights Agent at the office or offices of the Rights Agent designated for such purpose, together with payment of the aggregate Exercise Price for the total number of one one-thousandths of a share of Preferred Stock (or other securities, cash or other assets, as the case may be) as to which such surrendered Rights are then exercised, at or prior to the earlier of (i) the Close of Business on April 24, 2008 (the “Final Expiration Date”), (ii) the time at which the Rights are redeemed as provided in

Section 23 hereof, or (iii) the time at which such Rights are exchanged as provided in Section 24 hereof (the earlier of (i), (ii) or (iii) being herein referred to as the “Expiration Date”).”

2. Effectiveness. This Amendment shall be deemed effective as of the date first above written, as if executed on such date. Except as expressly set forth herein, this Amendment shall not by implication or otherwise alter, modify, amend or in any way affect any of the terms, conditions, obligations, covenants or agreements contained in the Rights Agreement, all of which are ratified and affirmed in all respects and shall continue in full force and effect and shall be otherwise unaffected.

3. Governing Law. This Amendment shall be deemed to be a contract made under the laws of the Commonwealth of Massachusetts and for all purposes shall be governed by and construed in accordance with the laws of such state applicable to contracts to be made and performed entirely within such state.

4. Counterparts. This Amendment may be executed in any number of counterparts, each of which shall for all purposes be deemed an original, and all of which together shall constitute but one and the same instrument.

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IN WITNESS WHEREOF, the parties have caused this Amendment to be duly executed as of the day and year first above written.

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