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                                                                   Exhibit 10.20

                                CUNO INCORPORATED
                     NONQUALIFIED DEFERRED COMPENSATION PLAN
                               FOR MARK G. KACHUR
                       (Effective as of November 1, 1997)

                                    ARTICLE I
                         ESTABLISHMENT AND CONSTRUCTION

1.1      Establishment. CUNO Incorporated (the "Company") establishes, effective
         as of January 1, 1997, this unfunded deferred compensation plan on
         behalf of Mark G. Kachur to be provided to supplement the Pension Plan
         for Salaried Employees of CUNO Incorporated ("Pension Plan"). This
         document shall be known as the "CUNO Incorporated Nonqualified Deferred
         Compensation Plan for Mark G. Kachur" (the "Plan").

1.2      Purpose. The Company maintains the Pension Plan which is intended to
         meet the requirements of a "qualified" retirement plan under Section
         401(a) of the Internal Revenue Code. The Pension Plan contains certain
         restrictions required by the Code that sometimes result in a diminution
         of benefits available to certain highly compensated employees. This
         Plan is established to replace some of the benefits lost due to this
         diminution and preclusion or upon a Change of Control. Also, this Plan
         is intended to be an unfunded deferred compensation plan for a member
         of a select group of management or highly compensated employees, as
         described in Sections 201(2), 301(a)(3), and 401(a)(1) of the Employee
         Retirement Income Security Act of 1974 ("ERISA").
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                                   ARTICLE II
                          DEFINITIONS AND CONSTRUCTION

2.1      Definitions. The following terms shall have the meaning stated below
         unless the context clearly indicates otherwise.

         (a)      "Committee" means the Compensation Committee described in
                  section 4.1 of this Plan, which has been delegated the
                  authority to administer this Plan.

         (b)      "Monthly Pay" means one-twelfth (1/12) of a Participant's
                  Compensation, as defined in the Pension Plan, received from
                  the Company and any Subsidiary, and shall include annual
                  bonuses paid under the target award programs ("MIP" and
                  "EMIP") but shall not include the premium under the stock
                  payout option of the target award programs, determined without
                  regard to the limitations of Section 401(a)(17) of the Code.

         (c)      "Participant" means Mark G. Kachur.

         (d)      "Years of Credited Service" means

                  (i) with respect to separation from service with the Company
                  or any Subsidiary prior to age sixty (60) after completion of
                  five (5) years of Service, his Credited Service under the
                  Pension Plan;

                  (ii) with respect to separation from service with the Company
                  or any Subsidiary at or after the attainment of age sixty (60)
                  but prior to attainment of age sixty-two (62), the greater of
                  twelve (12) years or actual Years of Service under the Pension
                  Plan;

                  (iii) with respect to separation from service with the Company
                  or any Subsidiary at or after the attainment of age sixty-two
                  (62) but prior to attainment of age sixty-five (65), the
                  greater of seventeen (17) years or actual Years of Service
                  under the Pension Plan;

                  (iv) with respect to separation from service with the Company
                       or any Subsidiary at or after attainment of age
                       sixty-five (65), twenty-five (25) years;

                  (v)  with respect to death after completion of five (5) years
                       of Service and prior to age sixty-five (65), his Years of
                       Credited Service determined as if he had separated from
                       service at age sixty-five (65) reduced by the number of
                       years and fractional years (1/12th for each complete
                       calendar month) by which his actual date of death
                       precedes the date as of which he would have attained age
                       sixty-five (65).

         Unless the context clearly indicates otherwise, terms not defined in
         this document shall have the meaning specified in the Pension Plan (if
         defined therein). Where the defined meaning is intended, the term is
         capitalized.

2.2      Gender and Number. Except when otherwise indicated by the context,
         words in the masculine gender shall include the feminine and neuter
         genders; the plural shall include the singular and the singular shall
         include the plural.

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2.3      Employment Rights. Establishment of the Plan shall not be construed to
         give the Participant the right to be retained by the Company or any
         Subsidiary or to any benefits not specifically provided by the Plan.

2.4      Severability. In the event any provision of the Plan shall be held
         invalid or illegal for any reason, any illegality or invalidity shall
         not affect the remaining parts of the Plan, but the Plan shall be
         construed and enforced as if the illegal or invalid provision had never
         been inserted, and the Company shall have the privilege and opportunity
         to correct and remedy such questions of illegality or invalidity by
         amendment as provided in the Plan.

2.5      Applicable Law. This Plan is fully exempt from Titles II, III and IV of
         ERISA. The Plan shall be governed and construed in accordance with
         Title I of ERISA and the laws of the State of Connecticut.

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                                   ARTICLE III
                                    BENEFITS

3.1      Amount of Retirement Benefits. Benefits will be payable to the
         Participant and will commence, at the election of the Participant as
         provided in Section 3.2, and shall equal the excess, if any, of (a)
         minus (b) where:

         (a)      is the benefit calculated under the Pension Plan as if the
                  provisions of the Pension Plan were administered using as the
                  Participant's Compensation the average of the Participant's
                  Monthly Pay during the highest three (3) consecutive years
                  during the ten (10) year period immediately preceding his
                  separation from service with the Company, using Years of
                  Credited Service and without regard to the benefit and
                  compensation limitations found in Code Sections 415 and
                  401(a)(17); and

         (b)      is the actual limited Pension Plan benefit which is payable to
                  such Participant.

3.2      Form and Commencement of Benefits. Benefits payable under this Plan
         shall be paid in the same manner and form and at the same time as
         benefits payable under the Pension Plan. Except as provided in Section
         3.4, the Participant will not voluntarily separate from service with
         the Company until after due consultation with the Company and the
         Committee.

3.3      Death Benefits. No death benefit shall be paid under this Plan except
         as provided in this Section.

         (a)      Spouse's Benefit. If the Participant dies after completion of
                  five (5) years of Service but before benefit payments begin
                  under the Plan, the Spouse, at the date of the Participant's
                  death, shall be paid a monthly benefit under the Plan in the
                  form of a life annuity calculated as under section 3.1
                  adjusted by applying the provisions of the Pre-Retirement
                  Survivor Annuity under the Pension Plan.

         (b)      If the Participant dies before benefit payments begin under
                  the Plan and has no Spouse, no death benefit shall be payable
                  under this Plan.

         (c)      If the Participant dies after benefit payments begin under
                  this Plan, a death benefit shall be payable under the Plan to
                  the Spouse of the Participant only if a death benefit is
                  payable to such Spouse under the form of payment selected by
                  the Participant.

3.4      Change of Control.

         (a)      "Change of Control" shall have the meaning as defined in the
                  agreement providing severance compensation to the Participant
                  upon a change in control of the management of the Company then
                  existing between the Company and the Participant (the
                  "Severance Compensation Agreement"). In the event of a Change
                  of Control, a monthly benefit shall be payable to the
                  Participant equal to the benefit calculated in Subsection
                  3.1(a) above adjusted as follows:

                            (i) Monthly Pay, for purposes of this Section 3.4,
                           shall mean the Participant's Monthly Pay during the
                           highest three (3) consecutive years

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                           during the ten (10) year period immediately preceding
                           his separation from service with the Company without
                           regard to the compensation limitation found in Code
                           Section 401(a)(17), and shall include annual bonuses
                           paid under the target award programs ("MIP" and
                           "EMIP") but shall not include the premium under the
                           stock payout option of the target award programs,
                           determined without regard to the limitations of
                           Section 401(a)(17) of the Code; provided, however,
                           that if a Change in Control occurs prior to the
                           Participant's third anniversary as Chief Executive
                           Officer of the Company, Monthly Pay, for purposes of
                           this Section 3.4, shall mean the Participant's
                           highest annualized Compensation plus the greater of
                           (1) an amount equal to the highest annual bonus paid
                           under the target award programs ("MIP" and "EMIP")
                           but shall not include the premium under the stock
                           payout option of the target award programs or (2) an
                           amount equal to the highest target level bonus under
                           the target award programs ("MIP" and "EMIP") but
                           shall not include the premium under the stock payout
                           option of the target award programs, determined
                           without regard to the limitations of Section
                           401(a)(17) of the Code.

                           (ii) Years of Credited Service, for purposes of this
                           Section 3.5 , shall mean the greater of (1) fifteen
                           (15) years or (2) the Years of Credited Service as
                           defined in Section 2.1(d) above.

         (b) Unless the Participant elects to defer the commencement of benefits
         to a later date, benefits under this Section 3.4 shall be payable to
         the Participant, beginning on the first day of the month coincident
         with or next following his separation from service with the Company or
         a Subsidiary.

         (c) Benefits payable under this Section 3.4 shall be paid in the same
         manner as benefits payable under the Pension Plan. However, in the sole
         discretion of the Participant, any benefit due to the Participant under
         the Plan may be paid in any of the forms of benefit payments available
         to the Participant under the Pension Plan or in the form of annual
         installments for a specified period of years. Each alternate form of
         payment shall be the Actuarial Equivalent of a single life annuity.
         Additionally, a Participant may elect to have a benefit due under this
         Section 3.4 paid in a single lump sum payment, provided notice thereof
         is received by the Compensation Committee prior to separation from
         service. The lump sum shall be the present value of the annuity
         calculated under this Plan using the basis defined below that produces
         the largest lump sum amount:

                  (1)      the UP-1984 mortality table and the PBGC interest
                           rate used for purposes of determining present value
                           of a lump sum distribution on plan termination as in
                           effect on the date of the Participant's election, or

                  (2)      the UP-1984 mortality table and the PBGC interest
                           rate used for purposes of determining present value
                           of a lump sum distribution on plan termination as in
                           effect on the date six (6) months prior to the date
                           of the Participant's election, or

                  (3)      the 1983 GAM mortality table and the applicable
                           interest rate promulgated by the Internal Revenue
                           Service under Code Section 417(e)(3) for the month in
                           which the Participant's election occurs, or

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                  (4)      the 1983 GAM mortality table and the applicable
                           interest rate promulgated by the Internal Revenue
                           Service under Code Section 417(e)(3) for the month
                           which is six (6) months prior to the Participant's
                           election.

The Participant may elect any combination of form of benefits not exceeding two
(2).

3.5      Early Distribution. Notwithstanding any other provision contained in
         this Plan, the Company shall make distributions to the Participant
         before such distributions otherwise are payable under this Plan if it
         determines upon the advice of counsel, based on a change in the Code, a
         published ruling or similar announcement issued by the Internal Revenue
         Service ("IRS"), a regulation issued by the Secretary of the Treasury
         or his delegate, a decision of a court of competent jurisdiction
         involving the Participant or a closing agreement involving the
         Participant that is approved by the IRS, that the Participant has
         recognized or will recognize income for federal income tax consequences
         with respect to amounts that are or will be distributable to him.

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                                   ARTICLE IV
                               GENERAL PROVISIONS

4.1      Administration. This Plan shall be administered by the Compensation
         Committee of the Board of Directors. The Compensation Committee shall
         have, to the extent appropriate, the same powers, rights, duties and
         obligations with respect to this Plan as the plan administrator under
         the Pension Plan has under such Pension Plan.

4.2      Finality of Determination. Except with respect to questions arising
         from benefits payable upon a Change of Control, the determination of
         the Compensation Committee as to any disputed questions arising under
         this Plan, including questions of construction and interpretation,
         shall be final, binding and conclusive upon all persons.

4.3      Expenses. The expenses of administering the Plan shall be borne by the
         Company.

4.4      Indemnification and Exculpation. The members of the Compensation
         Committee, its agents and officers, directors and employees of the
         Company and the Subsidiaries shall be indemnified and held harmless by
         the Company against and from any and all loss, cost, liability or
         expense that may be imposed upon or reasonably incurred by them in
         connection with or resulting from any claim, action, suit or proceeding
         to which they may be a party or in which they may be involved by reason
         of any action taken or failure to act under this Plan and against and
         from any and all amounts paid by them in settlement (with the Company's
         written approval) or paid by them in satisfaction of a judgment in any
         such action, suit or proceeding. The foregoing provision shall not be
         applicable to any person if the loss, cost, liability or expense is due
         to such person's gross negligence or willful misconduct.

4.5      Funding. While all benefits payable under the Plan constitute general
         corporate obligations, the Company shall establish a master rabbi trust
         for the benefit of the Participant, which trust shall be subject to the
         claims of the general creditors of the Company (and of any Subsidiary
         which has employed the Participant and become obligated under the Plan)
         in the event of such corporation's insolvency, to be used as a reserve
         for the discharge of the Company's or Subsidiary's obligations under
         the Plan to such Participant. The Company shall contribute to such
         trust an amount sufficient to fund the aggregate present value of all
         liabilities potentially owed to the Participant under this Plan and
         such funding shall occur no later than the date on which a Change of
         Control occurs. Any payments made to the Participant under the trust
         for his benefit shall reduce dollar for dollar the amount payable to
         the Participant from the general assets of the Company or Subsidiary.
         The amounts payable under the Plan shall be reflected on the accounting
         records of the Company or Subsidiary but shall not be construed to
         create or require the creation of a trust, custodial or escrow account,
         except as described above in this section. The Participant (or Spouse
         of Participant) shall not have any right, title or interest whatever in
         or to any investment reserves, accounts or funds that the Company or
         any Subsidiary may purchase, establish or accumulate to aid in
         providing benefits under this Plan. Nothing contained in this Plan, and
         no action taken pursuant to its provisions, shall create a trust or
         fiduciary relationship of any kind between the Company or any
         Subsidiary and the Participant or any other person, except as described
         above in this section. Neither the Participant nor Spouse of the
         Participant shall acquire any interest greater than that of an
         unsecured creditor.

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4.6      Corporate Action. Any action required of or permitted by the Company or
         any Subsidiary under this Plan shall be by resolution of its Board of
         Directors or any person or persons authorized by resolution of such
         Board of Directors.

4.7      Interests not Transferable. The interests of the Participant and his
         Spouse under the Plan are not subject to the claims of their creditors
         and may not be voluntarily or involuntarily transferred, assigned,
         alienated or encumbered.

4.8      Effect on Other Benefit Plans. Amounts credited or paid under this Plan
         shall not be considered to be compensation for the purposes of the
         Pension Plan maintained by the Company or any Subsidiary. The treatment
         of such amounts under other employee benefits plans shall be determined
         pursuant to the provisions of such plans.

4.9      Tax Liability. The Company or Subsidiary may withhold from any payment
         of benefits hereunder any taxes required to be withheld and such sum as
         such employer may reasonably estimate to be necessary to cover any
         taxes for which the Company or Subsidiary may be liable and which may
         be assessed with regard to such payment.

4.10     Legal Fees and Expenses. The Company shall pay all legal fees and
         expenses which the Participant may incur as a result of the Company's
         or any Subsidiary's contesting the validity, enforceability or the
         Participant's interpretation of, or determinations under, this Plan.

4.11     Successors and Assigns. This Plan and all of the obligations hereunder
         shall be binding on the successors and assigns of the Company.

4.12     Nonduplication of Benefits. The benefits payable under this Plan to a
         Participant are intended to replace such benefits payable to such
         Participant under the CUNO Incorporated Supplemental Executive
         Retirement Plan, and the Participant's benefits under such plan are
         terminated.

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                                    ARTICLE V
                            AMENDMENT AND TERMINATION

The Company by action of this Board of Directors reserves the right to amend
this Plan from time to time or to terminate the Plan at any time, but without
the written consent of the Participant, no such action may reduce or relieve the
Company or any Subsidiary of any obligation with respect to any benefit accrued
under the Plan by such Participant as of the date of such amendment or
termination.

IN WITNESS WHEREOF, the Company has caused this instrument to be executed by its
duly authorized officers on this 20th day of November, 1997.

                                            CUNO INCORPORATED
                                            By: /s/  Paul J. Powers
                                                -------------------------------
                                            Name:    Paul J. Powers
                                                 ------------------------------
                                            Title:   Chief Executive Officer
                                                  -----------------------------

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