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                                                                EXHIBIT 10.12(b)

                                EIGHTH AMENDMENT
                          DATED AS OF JANUARY 30, 2004
                                       TO
                           RECEIVABLES SALE AGREEMENT
                         DATED AS OF DECEMBER 21, 2001

         THIS EIGHTH AMENDMENT (the "Amendment"), dated as of January 30, 2004,
is entered into among PerkinElmer Receivables Company, as Seller (the "Seller"),
PerkinElmer, Inc., as Initial Collection Agent (the "Initial Collection Agent,"
and together with any successor thereto, the "Collection Agent"), the committed
purchasers party thereto (the "Committed Purchasers"), Windmill Funding
Corporation ("Windmill"), and ABN AMRO Bank N.V., as agent for the Purchasers
(the "Agent")

                                  WITNESSETH:

         WHEREAS, the Seller, the Initial Collection Agent, the Agent, the
Committed Purchasers and Windmill have heretofore executed and delivered a
Receivables Sale Agreement, dated as of December 21, 2001 (as amended,
supplemented or otherwise modified through the date hereof, the "Sale
Agreement"),

         WHEREAS, the parties hereto desire to amend the Sale Agreement as
provided herein;

         Now, THEREFORE, for good and valuable consideration, the receipt and
adequacy of which are hereby acknowledged, the parties hereto hereby agree that
the Sale Agreement shall be and is hereby amended as follows:

         Section 1. Subject to the following terms and conditions, including
without limitation the conditions precedent set forth in Section 2, upon
execution by the parties hereto in the space provided for that purpose below,
the Sale Agreement shall be, and is hereby, amended as follows:

                  (a)      The defined term "Liquidity Termination Date"
         appearing in Schedule I to the Sale Agreement is hereby amended by
         deleting the date "January 30, 2004" appearing in clause (d) thereof
         and inserting in its place the date "January 28, 2005."

                  (b)      Clause (f) of the defined term "Termination Event"
         appearing in Schedule I to the Sale Agreement is hereby amended in its
         entirety and as so amended shall read as follows:

                           "(f)     the average Delinquency Ratio for the three
                  most recent Settlement Periods exceeds 18%, the average
                  Default Ratio for the three most recent Settlement Periods
                  exceeds 10%, the average Dilution Ratio for the three most
                  recent Settlement Periods exceeds 6%, the Charge-Off Ratio for
                  the most recent Settlement Period exceeds 2% of the average
                  Turnover Ratio for the three most recent Settlement Periods
                  exceeds 90 days; or

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         Section  2. Section 1 of this Amendment shall become effective only
once the Agent has received (i) this Amendment duly executed by the Seller and
the Guarantor and (ii) the Fourth Amendment to Fee Letter duly executed by the
Seller, Windmill and the Agent.

         Section  3. The parties hereto consent to the execution and delivery of
that certain Second Amendment to Purchase and Sale Agreement by the parties
thereto.

         Section  4.1. To induce the Agent and the Purchasers to enter into this
Amendment, the Seller and Initial Collection Agent represent and warrant to the
Agent and the Purchasers that: (a) the representations and warranties contained
in the Transaction Documents, are true and correct in all material respects as
of the date hereof with the same effect as though made on the date hereof (it
being understood and agreed that any representation or warranty which by its
terms is made as of a specified date shall be required to be true and correct in
all material respects only as of such specified date); (b) no Potential
Termination Event exists; (c) this Amendment has been duly authorized by all
necessary corporate proceedings and duly executed and delivered by each of the
Seller and the Initial Collection Agent, and the Sale Agreement, as amended by
this Amendment, and each of the other Transaction Documents are the legal, valid
and binding obligations of the Seller and the Initial Collection Agent,
enforceable against the Seller and the Initial Collection Agent in accordance
with their respective terms, except as enforceability may be limited by
bankruptcy, insolvency or other similar laws of general application affecting
the enforcement of creditors' rights or by general principles of equity; and (d)
no consent, approval, authorization, order, registration or qualification with
any governmental authority is required for, and in the absence of which would
adversely effect, the legal and valid execution and delivery or performance by
the Seller or the Initial Collection Agent of this Amendment or the performance
by the Seller or the Initial Collection Agent of the Sale Agreement, as amended
by this Amendment, or any other Transaction Document to which they are a party.

         Section  4.2. This Amendment may be executed in any number of
counterparts and by the different parties on separate counterparts and each such
counterpart shall be deemed to be an original, but all such counterparts shall
together constitute but one and the same Amendment.

         Section  4.3. Except as specifically provided above, the Sale Agreement
and the other Transaction Documents shall remain in full force and effect and
are hereby ratified and confirmed in all respects. The execution, delivery, and
effectiveness of this Amendment shall not operate as a waiver of any right,
power, or remedy of any Agent or any Purchaser under the Sale Agreement or any
of the other Transaction Documents, nor constitute a waiver or modification of
any provision of any of the other Transaction Documents. All defined terms used
herein and not defined herein shall have the same meaning herein as in the Sale
Agreement. The Seller agrees to pay on demand all costs and expenses (including
reasonable fees and expenses of counsel) of or incurred by the Agent and each
Purchaser Agent in connection with the negotiation, preparation, execution and
delivery of this Amendment and the other documents related hereto.

         Section  4.4. This Amendment and the rights and obligations of the
parties hereunder shall be construed in accordance with and be governed by the
law of the State of Illinois.

                                       -2-
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         IN WITNESS WHEREOF, the parties have caused this Amendment to be
executed and delivered by their duly authorized officers as of the date first
above written.

                                          ABN AMRO BANK N.V., as the Agent, as
                                             the Committed Purchaser

                                          By: /s/ Patricia Luken
                                              ----------------------------------
                                          Title: Group Vice President

                                          By: /s/ Kevin G. Pilz
                                              ----------------------------------
                                                  Kevin G. Pilz
                                          Title: Vice President

                                          WINDMILL FUNDING CORPORATION

                                          By: /s/ [ILLEGIBLE]
                                              ----------------------------------
                                          Title: Vice President

                                          PERKINELMER RECEIVABLES COMPANY

                                          By: /s/ David C. Francisco
                                              ----------------------------------
                                          Title: Assistant Treasurer

                                          PERKINELMER, INC.

                                          By: /s/ Robert F. Friel
                                              ----------------------------------
                                          Title: SVP & CFO

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                     GUARANTOR'S ACKNOWLEDGMENT AND CONSENT

         The undersigned, PerkinElmer, Inc., has heretofore executed and
delivered the Limited Guaranty dated as of December 21, 2001 (the "Guaranty")
and hereby consents to the Amendment to the Sale Agreement as set forth above
and confirms that the Guaranty and all of the undersigned's obligations
thereunder remain in full force and effect. The undersigned further agrees that
the consent of the undersigned to any further amendments to the Sale Agreement
shall not be required as a result of this consent having been obtained, except
to the extent, if any, required by the Guaranty referred to above.

                                          PERKINELMER INC.

                                          By: /s/ Robert F. Friel
                                              ----------------------------------
                                          Title: SVP & CFO