Exhibit 10.7.1



                                                     April 27, 2004


DLJ Merchant Banking II, Inc.
11 Madison Avenue
New York, NY 10010

Hydrant Acquisition Corp.
c/o DLJ Merchant Banking II, Inc.
11 Madison Avenue
New York, NY 10010

Re:      Mueller Group, Inc.

Ladies and Gentlemen:

     Reference is hereby made to that certain letter agreement dated July 23,
1999 (the "Agreement"), a copy of which is attached hereto, between Credit
Suisse First Boston LLC, as successor to the interests of Donaldson, Lufkin &
Jenrette Securities Corporation under the Agreement ("CSFB"), and Hydrant
Acquisition Corp. (the "Company"). Capitalized terms used and not otherwise
defined herein shall have the meanings assigned to such terms in the Agreement.

     Subject to the following paragraph, CSFB hereby assigns as of the date
hereof all of its rights and obligations under the Agreement to DLJ Merchant
Banking II, Inc. ("Merchant Banking"), and Merchant Banking hereby assumes as of
the date hereof all of the rights and obligations of CSFB under the Agreement.
The Company hereby consents to such assignment and assumption, and from and
after the date hereof, the Company shall pay to Merchant Banking the advisory
fee contemplated by the Agreement.

     Notwithstanding the foregoing, in the event the Company determines to
pursue any Transaction during the term of the Agreement, CSFB shall retain the
right to act as the Company's exclusive financial advisor, sole placement agent,
sole initial purchaser or sole managing underwriter or sole dealer-manager (the
"Transaction Services"), as the case may be, with respect to each such
Transaction, and CSFB shall retain the right to receive fees in exchange for
such Transaction Services. Additionally, CSFB and its affiliates shall have the
rights and benefits provided by the indemnity set forth on Schedule I to the
Agreement (in addition to, and not to the exclusion of, Merchant Banking) for
(i) any

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advisory services rendered or failed to be rendered by CSFB to the Company
pursuant to the Agreement prior to the date hereof and (ii) any Transaction
Services rendered or failed to be rendered by CSFB to the Company pursuant to
the Agreement prior to the date hereof.

     Please confirm your agreement with the foregoing by signing in the space
indicated below and returning an executed copy of this letter to CSFB.

                                          Very truly yours,


                                          CREDIT SUISSE FIRST BOSTON LLC


                                          By:  /s/ Mark Levitt
                                              ----------------------------------
                                              Name:  Mark Levitt
                                              Title: Managing Director


Accepted and agreed to
this ___ day of __________, 2004


DLJ MERCHANT BANKING II, INC.


By:  /s/ Michael Isikow
    ---------------------------------
    Name:  Michael Isikow
    Title: Principal


Acknowledged and agreed to
this 28th day of April, 2004


HYDRANT ACQUISITION CORP.


By:  /s/ Darrell Jean
    --------------------------------
    Name:  Darrell Jean
    Title: Chief Financial Officer




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