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                                                                 Exhibit 10.33






                               WATERS CORPORATION
                           2003 EQUITY INCENTIVE PLAN

                             STOCK OPTION AGREEMENT

      THIS AGREEMENT dated as of December 8, 2004 between Waters Corporation, a
corporation organized under the laws of the State of Delaware (the "Company"),
and Brian K. Mazar (the "Optionee"), an employee of Waters Corporation.

      1.    GRANT OF OPTION. Pursuant and subject to the Company's 2003 Equity
Incentive Plan (as the same may be amended from time to time, the "Plan"), the
Company grants to you, the Optionee, an option (the "Option") to purchase from
the Company all or any part of a total of 15,000 shares (the "Optioned Shares")
of the common stock, par value $.01 per share, in the Company (the "Stock"), at
a price of $47.12 per share. The Grant Date of this Option is as of December 8,
2004.

      2.    CHARACTER OF OPTION. This Option is not intended to be treated as an
"incentive stock option" within the meaning of Section 422 of the Internal
Revenue Code of 1986, as amended.

      3.    DURATION OF OPTION. Subject to the following sentence, this Option
shall expire at 5:00 p.m. ET on the 10th anniversary of the Grant Date. However,
if your employment or other association with the Company and its Affiliates ends
before that date, this Option shall expire at 5:00 p.m. ET on the date specified
in the preceding sentence or, if earlier, the date specified in whichever of the
following applies :

            (a) If the termination of your employment or other association is on
account of your retirement, death or disability, the first anniversary of the
date your employment or other association ends.

            (b) If the termination of your employment or other association is
due to any other reason, thirty days after your employment or other association
ends.

      4.    EXERCISE OF OPTION.

            No portion of the Option is vested as of the date hereof. Except as
set forth in the Change of Control/Severance Agreement dated as of February 24,
2004 between the Company and the Optionee (the "Change of Control/Severance
Agreement"), on the first anniversary of the date hereof, 100% of the Option
granted hereunder will vest and such vested portion of the Option will be
exercisable. However, during any period that this Option remains outstanding
after your employment or other association with the Company and its Affiliates
ends, you may exercise it only to the extent it was exercisable immediately
prior to the end of your employment or other association.

            (b) The procedure for exercising this Option is described in Section
7.1(g) of the Plan. You may pay the exercise price due on exercise by (i) cash
or check payable to the order of the Company in an amount equal to the exercise
price of the shares to be purchased

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or, (ii) to the extent permitted by applicable law, through and under the terms
and conditions of any formal cashless exercise program authorized by the
Company.

      5.    TRANSFER OF OPTION. The Option granted hereunder may be transferred
or assigned by the Optionee to such Optionee's family member in accordance with
the provisions of Section 7.1 (f). of the Plan.

      6.    INCORPORATION OF PLAN TERMS. This Option is granted subject to all
of the applicable terms and provisions of the Plan, including but not limited to
the provision for acceleration of vesting of this Option set forth in Section 8
(Adjustment Provisions) and the limitations on the Company's obligation to
deliver Optioned Shares upon exercise set forth in Section 9 (Settlement of
Awards).

      7.    MISCELLANEOUS. This Agreement shall be construed and enforced in
accordance with the laws of the State of Delaware, without regard to the
conflict of laws principles thereof and shall be binding upon and inure to the
benefit of any successor or assign of the Company and any executor,
administrator, trustee, guardian, or other legal representative of you.
Capitalized terms used but not defined herein shall have the meaning assigned
under the Plan. This Agreement may be executed in one or more counterparts all
of which together shall constitute but one instrument.

      8.    TAX CONSEQUENCES. The Company makes no representation or warranty as
to the tax treatment to you of your receipt or exercise of this Option or upon
your sale or other disposition of the Optioned Shares. You should rely on your
own tax advisors for such advice.

      IN WITNESS WHEREOF, the parties have executed this Agreement as a sealed
instrument as of the date first above written.

WATERS CORPORATION

By: Douglas A. Berthiaume
Title: Chairman, President and Chief Executive Officer

EMPLOYEE

/s/ Brian K. Mazar
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Brian K. Mazar