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                                                                   EXHIBIT 10.12

                       [WILSON GREATBATCH LTD. LETTERHEAD]
                                November 1, 1996


MiniMed Inc.
12744 San Fernando Road
Sylmar, California 91342

Gentlemen:

           Reference is made to a certain Supply Agreement between you ("MMI")
and MiniMed Technologies Ltd. ("MMT"), and Wilson Greatbatch Ltd. ("WGL), dated
as of October 1, 1993 (the "Supply Agreement") and to a certain License
Agreement between MMI and WGL, dated as of October 1, 1993 (the "License
Agreement"). This letter is intended to set forth in writing certain amendments
to the Supply Agreement and License Agreement, respectively, as set forth below:

          1.        Section 1.5 of the Supply Agreement is hereby amended to
read in its entirety as follows:

                    "1.5 Products. "Products" shall mean any medical device now
          or hereafter manufactured by or for MMI, including, without
          limitation, an Insulin Device."

          2.        Article 2 of the Supply Agreement is hereby amended to read
in its entirety as follows:

                                   "ARTICLE 2
                                Purchase of Pumps

           2.1 Purchase Orders and Term (a) Subject to all of the terms and
           conditions of this Agreement (including this amended Article 2), WGL
           and MMI agree to a three (3) year supply arrangement to be effective
           January 1, 1996 through December 31, 1998 ("Termination Date"). The
           initial Termination Date may be automatically extended by one year
           upon the delivery to WGL by MMI of a purchase order for not less than
           five hundred (500) 05 Pumps not later than September 1, 1996 (which
           order has been received); and for one additional year upon the
           delivery to WGL by MMI of a purchase order for not less than five
           hundred (500) 05 Pumps not later than September 1, 1997. Thereafter,
           any extension of the Termination Date of this Agreement shall only be
           by mutual written agreement. If MMI fails to submit a purchase order
           by September 1 of any year during the Term for at least five hundred
           (500) 05 Pumps for the following year of the Term, there shall be no
           extension of the Term of this Agreement beyond the balance of the
           then-current three-year term. In addition, WGL, at its sole
           discretion, may (x) reject any such Order for less than five hundred
           (500) 05 Pumps and give MMI notice that the supply obligation of WGL
           shall terminate after completing and delivering any Pumps remaining
           under then-accepted Orders, or (y) accept such Order and give MMI
           notice that the supply obligation of WGL shall terminate after
           completing such Order.



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November 1, 1996
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     (b) For purposes hereof, the word "Term" shall mean the initial three
     calendar years of 1996, 1997 and 1998, and any additional years resulting
     from an extension of the initial three-year period as provided for in
     Paragraph (a) above, subject to earlier termination as provided in said
     Paragraph (a) and elsewhere in this Agreement.

     (c) MMI has issued and delivered to WGL a written purchase order to
     purchase seven hundred and fifty (750) WGL 05 Pumps for delivery during the
     first year of the Term ("First Order"). The First Order is to be delivered
     in accordance with the delivery schedule set forth therein. MMI has also
     delivered a purchase order to purchase five hundred (500) WGL 05 Pumps for
     delivery during 1997, which order shall be delivered in accordance
     therewith. On or prior to each September 1 hereafter during the Term, MMI
     may deliver a purchase order for additional WGL 05 Pumps. For purposes of
     this Agreement, the term "Orders" shall mean, collectively, the First Order
     and all additional purchase orders submitted by MMI in accordance with the
     Agreement. Any term or condition contained in MMI's form purchase order(s)
     (or any amendment thereto) which is in addition to or conflicts or is
     inconsistent with this Agreement shall be null and void, and this Agreement
     shall be controlling in all respects.

     2.2 Prices. (a) Subject to Paragraphs (b) through (d) of this Section 2.2,
     the purchase price for all WGL 05 Pumps during the Term shall be fifteen
     hundred dollars ($1,500) per pump unless the number of 05 Pumps ordered by
     MMI in any Order is less than seven hundred and fifty (750), in which case
     the price per pump shall be one thousand seven hundred and fifty dollars
     ($1,750).

     (b) If the Term of the Agreement is to extend beyond December 31, 1998,
     then WGL shall have the right to increase the price of all Pumps to be
     delivered after December 31, 1998 by an amount equal to the Base Prices
     multiplied by the percentage increase in the Consumer Price Index for the
     calendar month in which the Adjustment Date occurs over the Base CPI. WGL
     shall have the right to increase the Base Prices once only for each
     contract year; e.g., for Pumps sold in 1998, 1999, etc.

     (c)   For purposes hereof:

           (i)      "CPI Adjustment Date" shall mean June 1, 1998, June 1, 1999,
                    and June 1 of each year thereafter to the extent that the
                    Term shall have been extended.

           (ii)     "Consumer Price Index" shall mean the Revised Consumer Price
                    Index for Urban Wage Earners and Clerical Workers. All Items
                    (base index year 1982-84=100), for Buffalo, New York, as
                    published by the United States Department of Labor, Bureau
                    of Labor Statistics. If the manner



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November 1, 1996
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                    in which the Consumer Price Index is determined by the
                    Bureau of Labor Statistics shall be substantially revised,
                    including, without limitation, a change in the base index
                    year, an adjustment shall be made by WGL in such revised
                    index which would produce results equivalent, as nearly as
                    possible, to those which would have been obtained if such
                    Consumer Price Index had not been so revised. If the
                    Consumer Price Index shall become unavailable to the public
                    because publication is discontinued, or otherwise, or if
                    equivalent data is not readily available to enable WGL to
                    make the adjustment referred to in the preceding sentence,
                    then WGL will substitute therefor a comparable index based
                    upon charges in the cost of living or purchasing power of
                    the consumer dollar published by another governmental agency
                    or, if no such index shall be available, then a comparable
                    index published by a major bank or other financial
                    institution or by a university or recognized financial
                    publication.

          (iii)     "Base CPI" shall mean the Consumer Price Index for January,
                    1996.

          (iv)      "Base Prices" shall mean the $1,750 and $1,500 prices set
                    forth in Section 2.2(a) hereof.

     (d)  WGL shall give notice to MMI of any CPI adjustment promptly after the
     CPI Adjustment Date and, in any event, at least 30 days prior to September
     1 of 1998, September 1, 1999 and each September 1 thereafter to the extent
     that the Term shall have been extended, so that MMI can take any such
     adjustment into account in connection with placing its Orders under Section
     2. 1. MMI shall have 30 days after receipt of a CPI notice to object to any
     proposed increase in the Base Prices. If MMI does object to any such
     increase within said period, MMI shall notify WGL in writing ("Objection")
     and, if the parties cannot mutually agree on any proposed increase to Base
     Prices hereunder within 30 days after WGL's receipt of any such objection,
     the parties shall submit their dispute to an independent certified public
     accounting firm whose decision shall be final and binding. Any decision
     that an increase to the Base Price is warranted shall be retroactive to the
     beginning of the contract year as to which the price increase applies.

     2.3  No Modification of Order. (a) No Order shall be modified or cancelled.
     If MMI stops or refuses delivery of any Pumps covered by any Order prior to
     or on the applicable delivery date for the Pumps specified in the Order,
     then WGL shall invoice MMI for such Pumps on such date.




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November 1, 1996
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           (b) In the event MMI cancels any one of the Orders by written notice
           delivered to WGL, then WGL shall not be obligated to supply MMI with
           any further Pumps and may cancel this Agreement.

                     MMI's purchase obligations are subject to WGL having
           sufficient batteries compatible with the 05 Pumps. WGL represents and
           warrants that it has available, and will retain solely for
           availability to MMI in accordance with this Agreement, aminimum of at
           least 3,000 batteries which are compatible with the 05 Pumps.

           2.4 Quality. All Pumps covered by this Agreement will be manufactured
           under ISO 9001 system. WGL is certified to the standard British
           Standards Institute (BSI) certificate number FM 26911.

           2.5 Terms. Shipping terms are FOB Clarence, New York, U.S.A. Payment
           terms are Net 30 days after shipment.

           2.6 Continuing Supply. WGL and MiniMed shall in good faith discuss a
           continuing arrangement pursuant to which WGL would supply some Pumps
           for MMI as a second source of supply. If mutually agreed, the terms,
           conditions, price and time period for any such arrangement will be
           set forth in a written amendment to this Agreement or other written
           document, signed by both parties."

           3.  Article 7 of the Supply Agreement (as heretofore amended) is
hereby further amended as follows:

               (i)  The "Closing Date" as defined in Section 7.1 thereof is
                    changed from October 15, 1995 to October 15, 1998; and

               (ii) The term "Technology Election Date" as defined in Section
                    7.2(a) thereof is changed from September 1, 1995 to
                    September 1, 1998.

If the initial Termination Date of this Agreement is extended by one year
pursuant to Section 2.1(a) (as amended), and each time it is so extended, then
the Closing Date and the Technology Election Date referred to above shall each
also be extended by the same period of time.

           In addition, MMI agrees to deliver, to WGL, simultaneously with the
execution of this letter agreement, the securities of MMI that comprise the
License Fee (10,000 shares of common stock, $.01 par value, of MMI). In
connection with such delivery, WGL hereby restates and reaffirms to MMI the
representatives, warranties, acknowledgements and agreements appearing at
Exhibit C to the License Agreement.

           4.        Section 8.3 of the Supply Agreement is amended as follows:



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November 1, 1996
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                     (i)       Paragraph (a) is deleted.

                     (ii)      Paragraph (b) is amended to change the
                               introductory text of said paragraph to read in
                               its entirety as follows:

                               "MMI shall not be released from its obligations
                               to pay for 05 Pumps covered by any Order placed
                               under this Agreement in the event of a
                               termination of this Agreement by WGL under
                               Section 8.2(b) or under Section 8.2(a) if the
                               termination under Section 8.2(a) is based on any
                               of the following events:... "

Clauses (i) through (iii) that follow the foregoing text shall not be changed.

           5.        The License Agreement is hereby amended as follows:

                     (i)       Section 1.1 of the License Agreement is amended
                               to read in its entirety as follows:

                               "1.1 Affiliate. "Affiliate" of any entity shall
                               mean any other entity that directly, or
                               indirectly through one or more intermediaries,
                               controls, or is controlled by, or is under common
                               control with, the first entity. Control shall
                               mean owning more than thirty-four percent (34%)
                               of the total voting power of the entity.

                     (ii)      Section 1.2 of the License Agreement is hereby
                               amended to add a proviso at the end of said
                               Section 1.2, after the word MMI, as follows:

                               "; provided, however, that MMI shall not have any
                               right or license to use, and the term "Know-How"
                               shall not include, any information or know-how of
                               WGL relating to Pumps which is developed by WGL
                               after September 30, 1996, whether alone or
                               jointly with any third party, unless such
                               information or know-how (A) is directly used by
                               WGL in manufacturing or producing Pumps which are
                               purchased by MMI under the Supply Agreement or
                               (B) is developed by WGL alone or jointly with MMI
                               pursuant to a written order by MMI to develop
                               improvements to the Pumps, which order shall have
                               been acknowledged and accepted in writing by
                               WGL."

                     (iii)     Section 1.5 of the License Agreement is amended
                               to provide that "Pumps" shall include any 07
                               model Pump of WGL as well as 05 and 08 Pumps.



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November 1, 1996
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                     (iv)      Section 2.4(a) of the License Agreement is
                               amended to read in its entirety as follows:

                               "2.4 ADDITIONAL OBLIGATIONS AND CONSULTING
                               AGREEMENT. (a) With respect to the Know How, WGL
                               agrees to furnish MMI promptly after the
                               execution of this Agreement, at WGL expense,
                               copies of all documentation in written or
                               tangible form which compromises Know-How
                               hereunder that presently exists and was developed
                               in the normal course of WGL's engineering and
                               production. WGL further agrees to furnish to MMI
                               promptly after the date of Closing (as defined in
                               Section 6.2 hereof) any additional Know-How which
                               is directly related to the manufacture of the
                               Pumps theretofore purchased by MMI from WGL and
                               which may exist as of such time (but subject to
                               Section 1.2 as amended). In addition during the
                               nine-month period beginning upon MMI's written
                               notice thereof, which shall be given at least 60
                               days prior to the commencement of the Consulting
                               Period but not later than 60 days prior to the
                               Termination Date (as defined in the Supply
                               Agreement), as extended (the "Consulting
                               Period"), to the extent requested by MMI, WGL
                               agrees to consult with and provide to MMI up to
                               90 eight-hour man days of support and training as
                               to the Know How and the production of the Pumps,
                               by WGL personnel having knowledge of the Know
                               How. The first 30 eight-hour man days of such
                               services during the Consulting Period shall be at
                               no charge to MMI, and for the next 60 eight-hour
                               man days MMI shall be charged $500 per man day
                               except such charge shall be $1,000 per each man
                               day of WGL's program manager. In addition, MMI
                               shall promptly reimburse WGL for any travel and
                               living expense incurred by WGL personnel in
                               providing such services. The parties agree that
                               WGL shall not be required to maintain its current
                               Pump work force for purposes of this Section 2.4,
                               and shall only be required to make available WGL
                               personnel during the Consulting Period who are
                               knowledgeable and experienced with the Know How
                               and production of the Pumps. If the Initial
                               Termination Date of this Agreement is extended by
                               one year pursuant to Section 2. 1 (a) (as
                               amended), and each time it is so extended, then
                               the latest starting date for the Consulting
                               Period shall also be extended by one year and
                               shall run for a comparable 10-month period of
                               time."

                     (v)       Section 3.1 of the License Agreement is hereby
                               amended to provide that the Securities
                               constituting the License Fee (in the form of
                               10,000 shares of the common stock of MiniMed,
                               Inc.) are being issued and delivered to WGL
                               simultaneously with the execution of this letter
                               agreement. In connection with such delivery, WGL
                               hereby restates and reaffirms to



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November 1, 1996
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                     MMI the representatives, warranties, acknowledgements and
                     agreements appearing at Exhibit C to the License Agreement.

           (vi)      The "Royalty Date" as defined in Section 3.l(a) thereof is
                     changed from December 31, 1999 to December 31, 2002.

           (vii)     The date referred to in the first sentence of Section 5.1
                     thereof is changed from December 31, 1999 to December 31,
                     2002;

                     The month referred to in Section 5.5(b)(iii) thereof shall
                     continue to be July 1996; however, the "CPI Adjustment
                     Date" as defined in Section 5.5(b)(i) thereof is changed to
                     mean "July 1, 1997 and July 1 of each year thereafter
                     through July 1, 2002"; and

                     The date referred to in the first sentence of Section 5.6
                     thereof is changed from December 31, 1999 to December 31,
                     2002;

                     PROVIDED, HOWEVER, that the date December 31, 2002,
                     referred to in Sections 5.1, 5.5(b)(iii) and 5.6 of the
                     Agreement (as hereby amended), shall be extended each and
                     every time that the initial Termination Date of the Supply
                     Agreement between WGL and MMI shall be extended and by the
                     same period of time.

           (viii)    Section 5.2 is hereby amended to substitute for the term
                     "08 Pump" (in both places where it appears) the phrase "07
                     Pump or 08 Pump, as the case may be."

           (ix)      Sections 6.1 and 6.2 are hereby amended to read in their
                     entirety as follows:

                     "6.1      MMI PURCHASE OF EQUIPMENT. MMI agrees to purchase
                               subject to its inspection thereof at the time of
                               Closing (as hereinafter defined), and WGL agrees
                               to sell, certain equipment and tooling used by
                               WGL in the manufacture of 05 Pumps. At least 10
                               days prior to Closing, WGL shall deliver to MMI a
                               proposed list of the tooling and equipment to be
                               sold to MMI, which list shall be mutually agreed
                               upon prior to Closing (the "Equipment"). It is
                               agreed that there shall be included in the
                               Equipment which may be purchased at MMI's
                               election: (A) one of the laser welders currently
                               used by WGL in its pump motor assembly operation;
                               and (B) fixtures and associated custom tooling
                               that is used in the assembly of the 05 Pumps and
                               that is unique to such Pump. The



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November 1, 1996
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                               purchase price for the Equipment shall be
                               determined in accordance with Section 6.4 (the
                               "Purchase Price").

                               If WGL manufactures any 07 Pumps or 08 Pumps for
                               MMI pursuant to the Supply Agreement, WGL will
                               discuss with MMI the possible purchase by MMI of
                               tooling and equipment used in connection with
                               such manufacture; provided, however, that WGL
                               shall not be obligated to sell any such tooling
                               or equipment unless WGL and MMI enter into a
                               further written agreement setting forth the
                               specific assets to be sold and the terms and
                               conditions of sale.


                     6.2       Closing. The consummation of the purchase and
                               sale of the Equipment ("Closing") shall take
                               place at WGL's offices in Clarence, New York at a
                               time and on a date to be mutually agreed upon;
                               provided, however, that (i) such date shall be
                               the date on which WGL delivers the Equipment to
                               MMI (subject to the WHERE IS condition of Section
                               6.3); and (ii) subject to clause (i) above, such
                               date shall be no later than 30 days following the
                               last date on which Pumps are manufactured by WGL
                               for MMI. MMI may pay the Purchase Price in cash
                               or by delivery of securities of MMI the number of
                               which shall be in the same proportion to the
                               number of Securities (as defined in and as to be
                               delivered by MMI pursuant to Section 3.1 of this
                               License Agreement) as the Purchase Price bears to
                               $100,000."

              5.     The parties agree that MMT shall no longer be a party to
the Supply Agreement or the License Agreement, and MMI shall be fully liable for
all obligations of MMT, and shall have all rights of MMT, under both the Supply
Agreement and the License Agreement.

              6.     Except as specifically provided in this Agreement, the
Supply Agreement and License Agreement shall remain unchanged and in full force
and effect.



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MiniMed, Inc.
November 1, 1996
Page 9


           Please confirm you understanding and agreement to the foregoing by
countersigning this letter agreement and returning one copy to the undersigned.


Agreed to and Confirmed                          Agreed to and Confirmed
as of the date of this letter.                   as of the date of this letter.

MINIMED INC.                                     WILSON GREATBATCH LTD.


By     TERENCE H. GREGG                       By      EDWARD F. VOBORIL
  -----------------------------------           --------------------------------
   Terrence H. Gregg, President/COO             Edward F. Voboril, President/CE0