Document:

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                                                                   Exhibit 10.5D

                            AMENDMENT NO. 4 TO THE
                            ----------------------
                              MOORE MEDICAL CORP.
                    DEFINED BENEFIT PENSION PLAN AND TRUST
                    --------------------------------------

The Moore Medical Corp. Defined Benefit Pension Plan and Trust Agreement is
amended, effective August 18, 1999, as follows:

1.   Section 1.1, Trustees, is deleted in its entirety and the following Section
     -----------  --------                                               -------
     1.1, Trustees, is substituted therefor:
     ---  --------

     "1.1 TRUSTEES

            The following are hereby appointed to act as Trustees hereunder:

<TABLE>
<CAPTION>
                        NAME                                         ADDRESS
                        ----                                         -------
     <S>                                                       <C>
     (a)  The President of Moore Medical Corp.                 389 John Downey Drive,
                                                               New Britain, CT 06050

     (b)  An Executive Vice President of                       389 John Downey Drive,
          Moore Medical Corp., as designed by                  New Britain, CT 06050
          The President from time to time.

     (c)  An Senior Vice President of                          389 John Downey Drive
          Moore Medical Corp., as designated by the            New Britain, CT 06050
          President from time to time
</TABLE>

2.   The remainder of the Moore Medical Corp. Defined Benefit Pension Plan and
     Trust Agreement is ratified and affirmed.

IN WITNESS WHEREOF, the parties have executed this amendment this _______ day of
November, 1999.

                                        MOORE MEDICAL CORP.

                                        By  /s/ Linda M. Autore
                                          ---------------------
                                          Its President

                                            /s/ Linda M. Autore
                                          ---------------------
                                          Linda M. Autore, (President), Trustee

                                            /s/ Kenneth S. Kollmeyer
                                          --------------------------
                                          Kenneth S. Kollmeyer,
                                          (Executive Vice President -
                                          Operations), Trustee

                                            /s/ Joseph S. Savidge
                                          -----------------------
                                          Joseph P. Savidge,
                                          (Senior Vice President-Finance),
                                          Trustee<PAGE>

                                                                    Exhibit 10.8
                              MOORE MEDICAL CORP.
                                 P.O. Box 1500
                             389 John Downey Drive
                           New Britain, CT 06050-1500

                  Change of Control and Position Payment Plan

1.  Purpose

               The plan is designed to offer an incentive to selected key
               employees of the Company to continue in its employ by providing
               for severance payments if they should be affected by a "change in
               position" as a result of a "change of control or position."

2.  Eligibility

               The participants in this plan are the key employees of the
               Company selected for participation by the Chairman of the
               Board/President, as evidenced by his/her letter to the employee
               advising him or her of participation, and extent of
               participation, in the plan.  A participant's eligibility will
               terminate in the event of, and on, the material breach of his or
               her duties to the Company.

3.  Severance Payment Conditions

               Severance will be payable to participants if at least one of the
               following two defined conditions are satisfied: (a) a "change of
               control" on or before December 31, 2000, and (b) a "change in
               position" within twelve months after the control party change.

    (a)  A "change of control" is:

         (i)  either (x) any merger or consolidation of the Company into or with
              another corporation (other than a subsidiary of the Company), or
              (y) the acquisition by another person or entity of beneficial
              ownership (as defined in Rule 13d-3 under the Securities Exchange
              Act of 1934) of more than 50% of the common stock of the Company
              unless, immediately after such merger, consolidation or
              acquisition, the holders of common stock of the Company
              immediately prior to such merger, consolidation or acquisition own
              more than 50% of the voting capital stock of such other
              corporation or the voting interests of such person or entity; or
         (ii) any sale by the Company of substantially all of the assets and
              business of the Company for cash, stock, or any combination
              thereof, unless, immediately after such sale, the holders of
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               common stock of the Company immediately prior to such sale own
               50% or more of the voting capital stock of the acquiring
               corporation or, if the acquiring person or entity is not a
               corporation, more than 50% of the voting equity interests of such
               acquiring person or entity; or

         (iii) either (x) the election or removal of a majority of the directors
               of the Company as a result of a solicitation subject to Rule 14a-
               11 (or successor Rule) under the Securities Exchange Act of 1934
               relating to the election or removal of directors, or (y) the
               election of directors constituting a majority of the directors of
               the Company by other than the action of directors a majority to
               whom consist of Continuing Directors; for purposes hereof, a
               "Continuing Director" means a director (aa) for whose election
               the Company solicited proxies pursuant to a proxy statement under
               Regulation 14A of said Act, or (bb) who was elected by action of
               the directors a majority of whom were elected as described in
               clause (aa) hereof, or (cc) who was elected by action of
               directors a majority of whom were elected as described in clause
               (aa) and/or clause (bb) hereof.

         (b)   A participant's "change of position" is the termination of his or
               her employment by the Company (other than by reason of death,
               disability, or a material breach by the participant of his or her
               duties as an employee of the Company) or a substantial change in
               his or her duties. A participant will be considered to have had a
               substantial change in his or her duties only if:

         (I)   (x) the position level of the participant is lowered, or (y) the
               duties of the participant (if he or she held a corporate position
               level immediately prior to the change of control) are changed to
               (aa) primarily consist of new duties not based upon his or her
               training or experience, or (bb) include substantial duties
               performed immediately prior to the change of control by employees
               of the Company previously subordinate to the participant, or (z)
               the principal location of employment by the Company of the
               participant is changed to a location more than 75 miles from his
               or her residence (for purposes hereof, such residence is to be
               the participant's residence when the intent of any party to cause
               a "change of control" becomes actually known to the participant
               or is first publicly disclosed); and

               (ii) within 90 days after the occurrence of any of the events
               referred to in clause (x), (y), or (z) of Section 3(b) (i)
               hereof, he or she terminates his or her employment by the
               Company.
<PAGE>

4.  Severance Amount

          Each participant's severance amount will be the amount stated in the
          Chairman of the Board's/President's letter referred to in paragraph 2,
          above, as a percentage of the participant's annualized W-2 gross
          salary plus employee 401(k) contribution, but will not include any
          amount computed with respect to any incentive or bonus compensation,
          Company 401(k) contribution, car allowance, or other Company provided
          benefit. Payment of severance amounts will be made within 45 days
          after the quarter-end during which the later of the two conditions
          described in paragraph 3, above, occurs. In no event shall the amount
          payable under this paragraph exceed an amount which would (when
          aggregated with any other amounts which would be subject to the
          Section 280G or Section 162(m) provisions hereinafter referred to)
          result in any part of a payment otherwise to be made under this
          paragraph constituting a "parachute payment" under Section 280G of the
          Internal Revenue Code of 1986, as amended, or a payment which,
          pursuant to Section 162(m) of said Code, would not be deductible by
          the Company as compensation for federal income tax purposes.

5.  Administration; Determinations

The plan will be administered by the Board's Compensation Committee. All
interpretations and implementations of the plan by the Committee not expressly
inconsistent with the plan will be final and binding on the company and all
participants. Neither this plan nor any letter to a participant under Section 2
thereof can be changed orally and can be changed only by a writing specifically
making a change and signed by the Chairman of the Board/President of the
Company.

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