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                                                                   Exhibit 28.15


                               DATED July 16,1996


                           (1) D.R. WATKINS AND OTHERS

                              (2) WPI GROUP (U.K.)









                                    AGREEMENT
                          FOR THE SALE AND PURCHASE OF
                              THE SHARE CAPITAL OF
                            OYSTER TERMINALS LIMITED












                                  Slater Heelis
                               71 Princess Street
                                Manchester M2 4HL

                              Ref: 0.6853/l.JPO/CFD
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                                      INDEX
                                      -----


CLAUSES                                                                     PAGE
- - -------                                                                     ----

1        Interpretation                                                       3
2        Sale and Purchase                                                    3
3        Consideration                                                        4
4        Completion                                                           4
5        Warranties and Representations                                       6
6        Guarantees and Indemnities                                           7
7        Assignment                                                           7
8        Entire Agreement                                                     7
9        Continuance                                                          7
10       Further Assurance                                                    7
11       Governing Law                                                        8
12       Costs                                                                8
13       Announcements                                                        8
14       Notices                                                              8
15       Time of Essence                                                      9
16       Waiver of Rights                                                     9
17       Pension Surplus                                                     10
18       Vendors Undertaking                                                 10
19       Covenant                                                            10

SCHEDULES
- - ---------

First Schedule:            Vendors and Consideration
Second Schedule:           The Company
Third Schedule:            Interpretation
Fourth Schedule:           Warranties
Fifth Schedule:            The Properties
Sixth Schedule:            Limitations on Warranties

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THIS AGREEMENT is made the 16th day of July One Thousand nine hundred and ninety
six

BETWEEN:-

     (1)  THE PERSONS whose names and addresses are set out in Part I of the
          First Schedule ("the Vendors")

     (2)  WPI GROUP (U.K.) a company registered in England under number 3227062
          whose registered office is at Fairoak House, Church Road, Newport,
          Gwent. NP9 7EJ ("Purchaser")

WHEREAS:

     (A)  OYSTER TERMINALS LIMITED ("the Company") is a private company limited
          by shares incorporated in England under the Companies Act 1948 under
          company number 1167923 and further information concerning the Company
          is set in the Second Schedule.

     (B)  The Shareholders are either the beneficial holders or the trustees of
          the entire issued share capital of the Company and the Vendors have
          the right power and authority to sell and transfer such shares or
          procure the sale and transfer of free from all and any claims,
          charges, liens, encumbrances, options or equities thereto.

     (C)  The Vendors have agreed to sell or procure the sale of and the
          Purchaser has agreed to purchase the entire issued share capital of
          the Company on the terms and subject to the conditions set out in this
          Agreement and in the Schedules hereto ("the Agreement").
                                      

NOW IT IS HEREBY AGREED as follows:
- - -----------------------

     1    INTERPRETATION
          --------------

          In this Agreement the words and expressions defined in the Third
          Schedule hereto shall (unless the context otherwise requires) have the
          meanings thereby given to them and this Agreement shall be construed
          and interpreted accordingly.

     2    SALE AND PURCHASE
          -----------------

          2.1  Subject to the terms of this Agreement the Vendors shall sell (or
               procure the sale) with full title guarantee and the Purchaser
               shall purchase the Shares free from all Encumbrances and together
               with all rights now or hereafter attaching thereto.


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          2.2  The Purchaser shall not be obliged to complete the purchase
               unless the purchase of all the Shares is completed
               simultaneously.

          2.3  The Vendors hereby waive any pre-emption rights they may have
               relating to the Shares whether conferred by the Articles of
               Association of the Company or otherwise.

     3    CONSIDERATION
          -------------

          The consideration for the said sale and purchase of the Shares shall
          be the sum of [pound sterling]7,350,000 and shall be apportioned
          between the Shareholders in the manner set opposite their respective
          names in the First Schedule.

     4    COMPLETION
          ----------

          4.1  Subject to the provisions of this Clause completion of the sale
               and purchase of the Shares shall take place immediately following
               the exchange of this Agreement ("the Completion Date") at the
               offices of the Vendors' Solicitors whereupon:-

               4.1.1 the Vendors shall:-

                 4.1.1.1      deliver to the Purchaser

                         (a)  duly executed transfers of the Shares by the 
                              registered holders thereof in favour of the 
                              Purchaser and/or their nominee(s) together with 
                              the relative share certificates;

                         (b)  such waivers or consents as the Purchaser may 
                              require to enable the Purchaser or its nominees to
                              be registered as holders of the Shares;

                         (c)  the Disclosure Letter;

                         (d)  the Tax Deed.

                 4.1.1.2      cause such persons as the Purchaser may nominate 
                              to be validly appointed as additional directors of
                              the Company and upon such appointment forthwith 
                              cause each of the Directors of the Company and the
                              Secretary of the Company to retire from their

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                              respective offices and as employees each 
                              delivering to the Purchaser a letter under seal 
                              acknowledging that the person so retiring has no 
                              claim outstanding for compensation or otherwise 
                              and without any payment under the Employment 
                              Protection (Consolidation) Act 1978;

                    4.1.1.3   procure amendment of all authorities to the 
                              bankers of the Company relating to the bank 
                              accounts giving authority to such persons as the 
                              Purchaser may nominate to operate the same;

                    4.1.1.4   procure subject to stamping where necessary the
                              approval and registration of the transfers of the
                              Shares by the Board of the Company;

                    4.1.1.5   procure that the Company change its accounting
                              reference date to the date of the last Sunday in
                              September;

                    4.1.1.6   deliver to the Purchaser as agent for the 
                              Company:-

                              (a)  the title deeds relating to the Properties;

                              (b)  the statutory books, Certificates of 
                                   Incorporation, Certificates of Incorporation
                                   on Change of Name and the Common Seal of the 
                                   Company;

                              (c)  written confirmation from the relevant banks
                                   of all bank balances of the Company as at 12
                                   July 1996 together with bank reconciliation 
                                   statements as at the close of business on 15 
                                   July 1996.

            4.1.2   Upon compliance by the Vendors with the provisions of Clause
                    4.1.1 the Purchaser shall:

                    4.1.2.1   satisfy the consideration for the Shares by way of
                              telegraphic transfer payable to the Vendors' 
                              Solicitors (whose receipt shall be a good and 
                              absolute discharge to the Purchaser);


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                    4.1.2.2   deliver to the Vendors a duly executed counterpart
                              Tax Deed;

     5    WARRANTIES AND REPRESENTATIONS
          ------------------------------

          5.1  The Warrantors warrant and represent to the Purchaser in the
               terms of the Fourth Schedule hereto and acknowledge that the
               Purchaser is entering into this Agreement in reliance on each of
               the Warranties but no other warranty or representation.

          5.2  The Warranties are given subject to matters fairly disclosed in
               the Disclosure Letter.

          5.3  The Warranties shall be separate and independent and save as
               expressly provided shall not be limited by reference to any other
               sub-paragraph or anything in this Agreement other than Sixth
               Schedule.

          5.4  If any sum or sums payable pursuant to this Agreement as a result
               of a breach of any of the Warranties or pursuant to clause 19.1
               is subject to taxation in the hands of the Purchaser then the
               Vendors shall pay to the Purchaser such amount as will ensure
               that the net amount received in respect of any payment due from
               the Warrantors after such taxation is the same as it would have
               been were the payment not so subject to taxation.

          5.5  Where any statement in the Fourth Schedule or in the Disclosure
               Letter is qualified by the expression "so far as the Warrantors
               are aware" or the expression "to the best of the Warrantors'
               knowledge, information and belief" or any similar expression or
               wording of similar import, that statement shall (save where
               otherwise specifically stated) be deemed to include an additional
               statement that it has been made after due and careful enquiry.

          5.6  The rights and remedies of the Purchaser in respect of the
               Warranties shall not be affected by the sale and purchase of the
               Shares, by any knowledge of any matter (whether actual or
               constructive) any officer of the Purchaser may have in respect of
               the affairs of the Company, by any investigation made by or on
               behalf of the Purchaser into the affairs of the Company or by any
               other event or matter whatsoever, except a specific and duly
               authorised written waiver or release by the Purchaser.

          5.7  Any information supplied by or on behalf of the Company or its
               respective officers to the Warrantors or their agents or
               accountants, solicitors or other advisors in connection with the
               Warranties or the Disclosure Letter or otherwise in relation to
               the business and affairs of the Company shall not constitute a
               representation or warranty or guarantee as to the accuracy
               thereof by the Company and the Warrantor hereby waives any and
               all claims which they might otherwise have against the Company in
               respect thereof.


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     6    GUARANTEES AND INDEMNITIES
          --------------------------

          Each of the Vendors undertakes with the Purchaser that they will each
          use their reasonable endeavours to procure the release of the Company
          from all guarantees, indemnities and securities given by the Company
          in respect of his liabilities or of any Associate thereof and prior to
          the formal release of the Company from liability under or in
          connection with any such guarantees, indemnities and securities shall
          indemnify the Company and keep it indemnified from and against any
          payment made under any such guarantees, indemnities and securities and
          any expense, loss, damage, cost, claim or liability whatsoever which
          the Company may incur under or in connection therewith.

     7    ASSIGNMENT
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          This Agreement shall not be assignable save that the Purchaser shall
          be entitled to assign the same to a Related Company for so long as
          such entity shall remain a Related Company (but not otherwise) and
          accordingly the expression "the Purchaser" as used herein shall where
          the context so admits include any such assignee.

     8    ENTIRE AGREEMENT
          ----------------

          This Agreement (together with any documents referred to therein)
          constitutes the whole agreement between the parties hereto in
          connection with the Company and the sale and purchase of the Shares
          and it is expressly declared that no variations hereof shall be
          effective unless made in writing and agreed between all the parties
          hereto.

     9    CONTINUANCE
          -----------

          9.1  The provisions of this Agreement insofar as the same shall not
               have been performed at Completion shall remain in full force and
               effect notwithstanding Completion.

          9.2  Subject to Clause 7.1 above this Agreement shall be binding upon
               and enure for the benefit of the respective assigns successors
               and personal representatives of the parties.

     10   FURTHER ASSURANCE
          -----------------

          At any time after the date hereof the Vendors shall, at the request
          and cost of the Vendors, execute such documents and do such acts and
          things as the Purchaser may reasonably require for the purpose of
          vesting the Shares in the Purchaser or its nominee and giving to the
          Purchaser the full benefit of all the provisions of this Agreement.





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     11   GOVERNING LAW
          -------------

          This Agreement shall be governed by and construed in accordance with
          the laws of England and Wales and the parties hereby submit to the
          non-exclusive jurisdiction of the Courts of England and Wales.

     12   COSTS
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          Each party to this Agreement shall pay its own costs of and incidental
          to this Agreement and the sale and purchase hereby agreed to be made.

     13   ANNOUNCEMENTS
          -------------

          No announcement or circular in connection with the subject-matter of
          this Agreement (except any such announcement as may be required by the
          Purchaser to comply with the requirements of the NASDAQ/NMS) shall be
          made by or on behalf of the Vendors or the Purchaser without the prior
          written approval of the Vendors and the Purchaser as to its form and
          timing such consent not being unreasonably withheld or delayed.

     14   NOTICES
          -------

          14.1 Any notice required to be given under this Agreement shall be
               sufficiently given:

               (a)  if delivered personally; or

               (b)  if sent by courier; or

               (c)  if sent by facsimile copier or other electronic means of
                    communication; or

               (d)  by letter despatched by first class recorded delivery
                    pre-paid post (by air-mail if to an overseas address) in
                    which case such notice is deemed to be given at the close of
                    business on the next following Business Day,

          14.2 "Business Day" means any day (other than a Saturday or a Sunday)
               on which clearing banks are open for a full range of banking
               transactions in the country of the recipient.

          14.3 Any notice required to be given under this Agreement shall be
               sent:

               (a)  to the Vendors c/o the Vendors' Solicitors at:
                    Eversheds
                    Fitzalan House
                    Fitzalan Road
                    Cardiff CF2 1XW

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                  Facsimile No:          01222-464347
                  For the attention of:  Alan Whiteley

             (b)  to the Purchaser at:
                  WPI Group, Inc.
                  1155 Elm Street
                  Manchester
                  New Hampshire 03101
                  Facsimile No: 603 627 3150
                  For the attention of: Michael Tule, Vice President and General
                                                      Counsel

                  with a copy to the Purchaser's Solicitors at:
                  Slater Heelis
                  71 Princess Street
                  Manchester M2 4HL
                  Facsimile No:  0161 236 5282
                  For the attention of: Jeremy Orrell/Christopher Dunn

                  or to such other address or facsimile number as is
                  notified in writing from time to time by the Vendors
                  (or any one of them) or the Purchaser to the other
                  parties to this Agreement.

          14.4 The Vendors hereby irrevocably agree that for the purpose of any
               proceedings in the High Court of Justice in England and Wales
               process may be served on them or any of them by sending a copy
               thereof to Eversheds of Fitzalan House, Fitzalan Road, Cardiff,
               CF2 1XW (c/o Alan Whiteley) by first class prepaid letter sent
               through the post to such address and such process shall be deemed
               to have been served 48 hours after the time at which the envelope
               containing the same was posted (excluding Saturdays, Sundays and
               Public Holidays) and in proving such service it shall be
               sufficient to prove that an envelope containing the same was
               properly addressed, stamped and placed in the post to Eversheds
               aforesaid.

     15   TIME OF ESSENCE
          ---------------

          Any date or period mentioned in this Agreement may be extended by
          mutual written agreement between the parties hereto, but as regards
          any date or period (whether or not extended as aforesaid) time shall
          be of the essence of this Agreement.

     16   WAIVER OF RIGHTS
          ----------------

          No waiver by any of the parties of any of the requirements hereof or
          of any of its rights hereunder shall have effect unless given in
          writing and signed by the party or by the party or

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          by the director or other duly authorised officer of such party.

     17   PENSION SURPLUS
          ---------------

          17.1 In the event of the Company receiving a payment of surplus fund
               ("the Net Surplus") from the Oyster Terminals Limited Executive
               Pension Scheme (SSAS) established by a deed dated 13 January 1984
               and made between the Company (1) and D. R. Watkins and Others (2)
               the Company agrees to pay an amount equal to the Net Surplus less
               any Relevant Tax due to Clifford Edwin Allen or if he is no
               longer living to those members of his family, as are nominated by
               him in writing or in default thereof to his personal
               representatives within twenty-one days of the Company receiving
               the Payment.

          17.2 In this clause "Relevant Tax" shall mean any tax imposed on the
               Company in respect of the receipt of the Net Surplus or the
               payment of a part of the Net Surplus to any person in accordance
               with this clause.

     18   VENDORS' UNDERTAKING
          --------------------

          The Vendors undertake to give all reasonable assistance to the
          Purchaser and/or the Company in obtaining a certificate of lawfulness
          of existing use pursuant to section 191 of the Town and Country
          Planning Act 1990 in relation to the Property.

     19   COVENANT
          --------

          19.1 The Warrantors hereby covenant with the Purchaser to pay to the
               Purchaser such sums as would if paid to the Company indemnify and
               keep indemnified the Company against any and all losses,
               liabilities, damages, awards and reasonable costs and expenses
               (including legal and professional expenses) of whatever nature
               and howsoever arising against or incurred by the Company (but
               after giving credit for any reduction in Taxation (as defined in
               the Tax Deed) as a result of any such being incurred or paid by
               the Company) in connection with or in relation to the alleged
               termination of the agency agreement between Escom International
               Marketing Inc ("Escom") and the Company, the action in the United
               States District Court for the Central District of California by
               Escom against the Company or otherwise in connection with the
               subject matter of the claim.

          19.2 Notwithstanding any other provision of this Clause 19 the
               liability of the Warrantors, under this Clause 19, shall be
               limited in accordance with the provisions of paragraphs 1(c), 2
               and 4 of the Sixth Schedule, and so that they shall not have any
               liability to the extent the subject matter of the claim has been
               recovered pursuant to the Tax Deed.


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I N  W I T N E S S whereof this Agreement has been entered into the day and year
first before written



SIGNED by /s/DOUGLAS RICHARD WATKINS
in the presence of:-

/s/Alan Whiteley
Solicitor
Cardiff


SIGNED by /s/CLIFFORD EDWIN ALLEN
in the presence of:-

/s/Alan Whiteley
Solicitor
Cardiff

SIGNED by /s/MICHAEL FOSTER
duly authorised signatory for and
on behalf of WPI GROUP (U.K.)
in the presence of:-

/s/Christopher Dunn
Solicitor
Manchester






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