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                                                                    EXHIBIT 10.6


                               WATERS CORPORATION

                     AMENDED AND RESTATED 1996 NON-EMPLOYEE

                           DIRECTOR STOCK OPTION PLAN

I.       PURPOSE.

         The purpose of the Waters Corporation Amended and Restated 1996
Non-Employee Director Stock Option Plan (the "PLAN") is to promote the interests
of the Waters Corporation (the "COMPANY") by providing an inducement to obtain
and retain the services of qualified persons as members of the Company's Board
of Directors (the "BOARD"), to align more closely the interests of such persons
with the interests of the Company's stockholders by providing a significant
portion of the compensation provided to such persons in the form of equity
securities of the Company, to secure for the Company and its stockholders the
benefits inherent in increased share price, and to maintain competitiveness with
other corporations conducting businesses comparable to that of the Company.

II.      ADMINISTRATION.

         The Plan shall be administered by the Compensation Committee of the
Board (the "COMMITTEE"). The Committee shall have full power to construe and
interpret the Plan and Options granted hereunder, to establish and amend rules
for its administration and to correct any defect or omission and to reconcile
any inconsistency in the Plan or in any Option granted hereunder to the extent
the Committee deems desirable to carry the Plan or any Option granted hereunder
into effect. Any decisions of the Committee in the administration of the Plan
shall be final and conclusive. The Committee may authorize any one or more of
its members, the secretary of the Committee or any officer of the Company to
execute and deliver documents on behalf of the Committee. Each member of the
Committee, and, to the extent provided by the Committee, any other person to
whom duties or powers shall be delegated in connection with the Plan, shall
incur no liability with respect to any action taken or omitted to be taken in
connection with the Plan and shall be fully protected in relying in good faith
upon the advice of counsel, to the fullest extent permitted under applicable
law.

III.     ELIGIBILITY.

         Participation in the Plan shall be automatic and nondiscretionary with
respect to each current and future Non-Employee Director and each Non-Employee
Director shall be eligible to participate in the Plan.

IV.      LIMITATION ON AGGREGATE SHARES.

         A. MAXIMUM NUMBER OF SHARES. The aggregate maximum number of Shares
that may be granted pursuant to the Plan or issued upon exercise of Options
granted pursuant to the Plan shall be 100,000 shares. Such maximum number of
Shares is subject to adjustment under the provisions of Section IV.B. The Shares
to


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be issued upon exercise of Options may be authorized but unissued Shares or
Shares previously issued which have been reacquired by the Company. In the event
any Option shall, for any reason, terminate or expire or be surrendered without
having been exercised in full, the Shares subject to such Option but not
purchased thereunder shall be available for future Options to be granted under
the Plan.

         B. ADJUSTMENT. The maximum number of Shares referred to in Section
IV.A, and the number of Shares which may be purchased under any outstanding
Option granted under Section VI of the Plan shall be proportionately adjusted
for any increase or decrease in the number of issued and outstanding Shares
occurring after June 10, 1999 as the result of (1) the declaration and payment
of a dividend payable in Common Stock, or the division of the Common Stock
outstanding at the date hereof (or the date of the grant of any such outstanding
Option, as applicable) into a greater number of Shares without the receipt of
consideration therefor by the Company, or any other increase in the number of
such Shares of the Company outstanding at the date hereof (or the date of the
grant of any such outstanding Option, as applicable) which is effective without
the receipt of consideration therefor by the Company (exclusive of any Shares
granted by the Company to employees of the Company or any of its Subsidiaries
without receipt of separate consideration by the Company), or (ii) the
consolidation of the Shares outstanding at the date hereof (or the date of the
grant of any such outstanding Option, as applicable) into a smaller number of
Shares without the payment of consideration thereof by the Company, or any other
decrease in the number of such Shares outstanding at the date hereof (or the
date of the grant of any such outstanding Option, as applicable) effected
without the payment of consideration by the Company; PROVIDED, HOWEVER, that the
total option price for all Shares which may be purchased upon the exercise of
any Option granted pursuant to the Plan (computed by multiplying the number of
Shares originally purchasable thereunder, reduced by the number of such Shares
which have theretofore been purchased thereunder, by the original option price
per share before any of the adjustments herein provided for) shall not be
changed.

         In the event of a change in the Common Stock as presently constituted
which is limited to a change of the Company's authorized shares with a par value
into the same number of shares with a different par value or without par value,
the shares resulting from any such change will be deemed to be the Common Stock
within the meaning of this Plan and no adjustment will be required pursuant to
this Section IV.B.

         The foregoing adjustments shall be made by the Committee, whose
determination in that respect shall be final, binding and conclusive. Except as
expressly provided in this Section IV.B, a Non-Employee Director shall have no
rights by reason of any subdivision or consolidation of shares of stock of any
class or the payment of any stock dividend or any other increase or decrease in
the number of shares of stock of any class.

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V.       DEFINITIONS.

         The following terms shall have the meanings set forth below when used
herein:

         "CODE" means the Internal Revenue Code of 1986, as amended.

         "COMMITTEE" means the Compensation Committee of the Board, any
successor committee of the Board performing similar functions or, in the absence
of such a committee, the Board.

         "COMMON STOCK" means the Common Stock, par value $.01 per share, of the
Company.

         "DISABILITY" means a mental or physical condition which, in the opinion
of the Committee, renders a Non-Employee Director unable or incompetent to carry
out his or her duties as a member of the Board and which is expected to be
permanent or for an indefinite duration.

         "ERISA" means the Employee Retirement Income Security Act of 1974, as
amended.

         "EXCHANGE ACT" means the Securities Exchange Act of 1934, as amended.

         "FAIR MARKET VALUE" of any Share means, as of any applicable date, the
mean between the high and low prices of the Shares as reported on the New York
Stock Exchange, or if no such reported sale of the Shares shall have occurred on
such date, on the next succeeding date on which there was such a reported sale.

         "INITIAL ELECTION DATE" means, for each Non-Employee Director, the
later to occur of (i) the date the Plan is adopted by the Board, and (ii) the
date of such member's initial election or appointment to the Board.

         "NON-EMPLOYEE DIRECTOR" means each member of the Board who is not an
officer or employee of the Company or any of its Subsidiaries.

         "OPTION" means an option to purchase Shares.

         "SHARES" means shares of Common Stock.

         "SUBSIDIARY" means any partnership, corporation, association, limited
liability company, joint stock company, trust, joint venture, unincorporated
organization or other business entity of which (i) if a corporation, a majority
of the total voting power of shares of stock entitled (without regard to the
occurrence of any contingency) to vote in the election of directors, managers or
trustees thereof is at the time owned or controlled, directly or indirectly, by
the Company or one or more of the other Subsidiaries of the Company or a
combination thereof, or (ii) if a partnership, association, limited liability
company, joint stock company, trust, joint


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venture, unincorporated organization or other business entity, a majority of the
partnership or other similar equity ownership interest thereof is at the time
owned or controlled, directly or indirectly, by the Company or one or more
Subsidiaries of the Company or a combination thereof. For purposes hereof, the
Company or a Subsidiary shall be deemed to have a majority ownership interest in
a partnership, association, limited liability company, joint stock company,
trust, joint venture, unincorporated organization or other business entity if
the Company or such Subsidiary shall be allocated a majority of partnership,
association, limited liability company, joint stock company, trust, joint
venture, unincorporated organization or other business entity gains or losses or
shall be or control the managing director, the trustee, the manager or the
general partner of such partnership, association, limited liability company,
joint stock company, trust, joint venture, unincorporated organization or other
business entity.

VI.      FORMULA STOCK OPTION GRANTS FOR NON-EMPLOYEE DIRECTORS.

         A. ANNUAL GRANT OF OPTIONS. Beginning December 1, 1997, on December 1
of each year through and including December 1, 1998, 1,000 options shall
automatically be granted to each Non-Employee Director serving on the Board on
such date. Beginning January 1, 2000, on January 1 of each year, 2,000 options,
subject to adjustment immediately upon the occurrence of any of the events
described in Sections IV.B.(i) and/or IV.B.(ii) hereof occurring after December
9, 1999, such adjustment to be made in accordance with the provisions of Section
IV.B. hereof, shall automatically be granted to each Non-Employee Director
serving on the Board on such date (collectively, the "Annual Options").

         B. INITIAL GRANT OF OPTIONS. On July 1, 1996, each Non-Employee
Director serving on the Board on such date shall automatically be granted 1,000
options (the "Initial Options"), which shall be exercisable on or after July 1,
1997. If after July 1, 1996, a Non-Employee Director is initially elected or
appointed to the Board effective on any date other than January 1, such
Non-Employee Director shall automatically be granted at the time of such
appointment or election, 1,000 Options if such date is prior to December 9,
1999, and 2000 options if such date is on or after December 9, 1999, in the
latter case subject to adjustment immediately upon the occurrence of any of the
events described in Sections IV.B.(i) and/or IV.B.(ii) hereof occurring after
December 9, 1999, such adjustment to be made in accordance with the provisions
of Section IV.B. hereof, which options shall be exercisable after the one-year
anniversary of such grant.

         C. OPTION EXERCISE PRICE. The exercise price per Share for each Option
shall be the Fair Market Value of a Share on the date of the grant, subject to
Section IV.B.

         D. TERM OF OPTIONS. Each Option shall be exercisable for ten years
after the date of grant, subject to Section VI.B.

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         E.       CONDITIONS AND LIMITATIONS ON EXERCISE.

         Unless otherwise approved by the Board in its discretion:

         (i) VESTING.

                  a) Each Initial Option shall vest upon the first anniversary
         of the date of grant.

                  b) Twenty percent of each grant of Annual Options shall vest
         on each December 1, as to Annual Options granted prior to January 1,
         2000, and on each January 1 as to Annual Options granted on or after
         January 1, 2000, in each case, of each of the five years following the
         grant of such Annual Options beginning on the one-year anniversary of
         such grant.

                  c) Upon the termination of a Non-Employee Director's tenure
         for any reason, the unvested portion of any outstanding Options shall
         expire.

         (ii) EXERCISE. Each Option shall be exercisable in one or more
         installments and shall not exercisable for less than 100 Shares, unless
         the exercise represents the entire remaining exercisable balance of a
         grant or grants. Each Option shall be exercised by delivery to the
         Company of written notice of intent to purchase a specific number of
         Shares subject to the Option. The option price of any Shares as to
         which an Option shall be exercised shall be paid in full at the time of
         the exercise. Payment may, at the election of the Non-Employee
         Director, be made in any one or any combination of the following forms:

                  a) wire transfer of funds or check in such form as may be
         satisfactory to the Committee;

                  b) Shares (so long as such shares were held by the
         Non-Employee Director for a period of six months prior to the date of
         exercise) valued at their Fair Market Value on the date of exercise or,
         if the date of exercise is not a business day, the next succeeding
         business day; or

                  c) through simultaneous sale through a broker of unrestricted
         Shares acquired on exercise, as permitted under Regulation T of the
         Federal Reserve Board.

         F.       ADDITIONAL PROVISIONS.

                  (i) ACCELERATED EXPIRATION OF OPTIONS UPON TERMINATION OF
         DIRECTORSHIP. Upon the termination of a Non-Employee Director's tenure
         for any reason other than death, each outstanding vested and
         unexercised Option shall expire 60 days after the date of such
         termination. In the case of a Non-Employee Director's death while in
         office, each outstanding vested and


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         unexercised Option shall expire one year after such Non-Employee
         Director's death.

                  (ii) SALE OF THE COMPANY. In the event of a merger of the
         Company with or into another corporation constituting a change of
         control of the Company, a sale of all or substantially all of the
         Company's assets or a sale of a majority of the Company's outstanding
         voting securities (a "SALE OF THE COMPANY"), the Options may be assumed
         by the successor corporation or a parent of such successor corporation
         or substantially equivalent options may be substituted by the successor
         corporation or a parent of such successor corporation, and if the
         successor corporation does not assume the Options or substitute
         options, then all outstanding and unvested Options shall become
         immediately exercisable and all outstanding Options shall terminate if
         not exercised as of the date of the Sale of the Company (or other
         prescribed period of time). The Company shall provide at least 30 days
         prior written notice of the Sale of the Company to the holders of all
         outstanding Options, which notice shall state whether (a) the Options
         will be assumed by the successor corporation or substantially
         equivalent options will be substituted by the successor corporation, or
         (b) the Options are thereafter vested and exercisable and will
         terminate if not exercised as of the date of the Sale of the Company
         (or other prescribed period of time).

                  (iii) LIQUIDATION OR DISSOLUTION. In the event of the
         liquidation or dissolution of the Company, Options shall terminate
         immediately prior to the liquidation or dissolution.

         G. NON-QUALIFIED STOCK OPTIONS. All Options granted under the Plan
shall be nonqualified options not entitled to special tax treatment under Code
Section 422, as may be amended from time to time.

VII.     MISCELLANEOUS PROVISIONS.

         A. RIGHTS OF NON-EMPLOYEE DIRECTORS. No Non-Employee Director shall be
entitled under the Plan to voting rights, dividends or other rights of a
stockholder prior to the issuance of Common Stock. Neither the Plan nor any
action taken hereunder shall be construed as giving any Non-Employee Director
any right to be retained in the service of the Company.

         B.       LIMITATIONS ON TRANSFER AND EXERCISE.

                  (i) Except as provided in Section VII.B.(ii) below, all
         Options granted under the Plan shall not be transferable by the
         Non-Employee Director, other than by will or the laws of descent and
         distribution or pursuant to a qualified domestic relations order, as
         defined by Section 1 eT Seq, of the Code, Title I of ERISA or the
         rules and regulations thereunder, and shall be exercisable during the
         Non-Employee Director's lifetime only by such Non-Employee Director or
         by such Non-Employee Director's guardian or other legal
         representative.


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                  (ii) The Committee, in its sole discretion, may establish, as
         permitted by applicable law, rules and conditions under which the
         Non-Employee Director may transfer Options to such individuals or types
         of trusts that the Committee may determine to be eligible for transfer
         (each a "PERMITTED TRANSFEREE"), and following such determination any
         Options transferred to a Permitted Transferee may be exercised by such
         Permitted Transferee subject to the terms and conditions set forth
         herein.

         C. COMPLIANCE WITH LAWS. No Options shall be issued hereunder unless
counsel for the Company shall be satisfied that such issuance will be in
compliance with applicable federal, state, local and foreign securities,
securities exchange and other applicable laws and requirements. Each Option
granted hereunder shall be subject to the requirement that if at any time the
Committee shall determine, in its discretion, that the listing, registration or
qualification of the Shares subject to the Option upon any securities exchange
or under any state or federal securities or other law or regulation, or the
consent or approval of any governmental regulatory body, is necessary or
desirable as a condition to or in connection with the granting of such Option or
the issuance or purchase of Shares thereunder, no such Option may be exercised
or paid in Common Stock, in whole or in part, unless such listing, registration,
qualification, consent or approval shall have been effected or obtained free of
any conditions not acceptable to the Committee. The holder of such Option will
supply the Company with such certificates, representations and information as
the Company shall request and shall otherwise cooperate with the Company in
obtaining such listing, registration, qualification, consent or approval. The
Committee may at any time impose any limitations upon the exercise of an Option
or the sale of the Common Stock issued upon exercise of an Option that, in the
Committee's discretion, are necessary or desirable in order to comply with
Section 16(b) of the Exchange Act and the rules and regulations thereunder.

         D. PAYMENT OF WITHHOLDING TAX. It shall be a condition to the
obligation of the Company to issue Shares upon exercise of Options granted
hereunder that the participant pay to the Company, upon its demand, such amount
as may be requested by the Company for the purpose of satisfying any liability
to withhold federal, state, local or foreign income or other taxes. If the
amount requested is not paid, the Company shall have no obligation to issue, and
the Non-Employee Director shall have no right to receive, Shares.

         E. EXPENSES. The expenses of the Plan shall be borne by the Company and
its Subsidiaries.

         F. DEEMED ACCEPTANCE, RATIFICATION AND CONSENT. By accepting any Common
Stock hereunder or other benefit under the Plan, each Non-Employee Director and
each person claiming under or through him or her shall be conclusively deemed to
have indicated his or her acceptance and ratification of, and consent to, any
action taken under the Plan by the Company, the Board or the Committee.


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         G. SECURITIES ACT REGISTRATION. The Company shall use its best efforts
to cause to be filed under the Securities Act of 1933, as amended, a
registration statement covering the Shares issued, and issuable upon exercise of
options granted, under the Plan.

         H. GOVERNING LAW. The provisions of the Plan shall be governed by and
construed in accordance with the laws of the State of Delaware.

         I. HEADINGS; CONSTRUCTION. Headings are given to the sections of the
Plan solely as a convenience to facilitate reference. Such headings, numbering
and paragraphing shall not in any case be deemed in any way material or relevant
to the construction of the Plan or any provisions hereof. The use of the
singular shall also include within its meaning the plural, where appropriate,
and VICE VERSA.

VIII.    AMENDMENT.

         The Plan may be amended at any time and from time to time by resolution
of the Board as the Board shall deem advisable; PROVIDED, HOWEVER, that no
amendment shall become effective without stockholder approval if such
stockholder approval is required by law, rule or regulation; and PROVIDED
FURTHER, that to the extent required by Rule 16b-3 under Section 16 of the
Exchange Act, Plan provisions shall not be amended more than once every six
months, except that the foregoing shall not preclude any amendment to comport
with changes in the Code, ERISA or the rules thereunder. No amendment of the
Plan shall materially and adversely affect any right of any participant with
respect to any Options or Shares theretofore granted under the Plan without such
participant's written consent, except for any modifications required to maintain
compliance with any federal or state statute or regulation.

IX.      TERMINATION.

         The Plan shall terminate upon the earlier of the following dates or
events to occur:

                  (i) upon the adoption of a resolution of the Board terminating
         the Plan; and

                  (ii) ten years from the date the Plan is initially approved
         and adopted by the stockholders of the Company in accordance with
         Article X.

         Except as specifically provided herein, no termination of the Plan
shall materially and adversely affect any of the rights or obligations of any
person without his or her consent with respect to any Options theretofore
granted under the Plan.


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X.       STOCKHOLDER APPROVAL AND ADOPTION.

         The Plan is dated April 1, 1996 and was approved by the Board of
Directors on February 26, 1996. The Plan was approved and adopted by the
stockholders of the Company at a meeting of the stockholders of the Company held
May 7, 1996.