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                                                                     Exhibit 4.2

                               First AMENDMENT TO

                                    WARRANTS



         This First  Amendment  (this  "AMENDMENT") to Warrants is entered into,
dated and  effective as of August 22, 2003,  among  Stratasys,  Inc., a Delaware
corporation  (the  "COMPANY"),  and each  purchaser  identified on the signature
pages hereto (each, a "PURCHASER" and collectively, the "PURCHASERS").

         WHEREAS,  the Company  and each  Purchaser  is a party to that  certain
Securities  Purchase  Agreement  dated as of  August  17,  2003  (the  "PURCHASE
AGREEMENT");

         WHEREAS,  pursuant to the Purchase Agreement the Company issued to each
Purchaser the a Warrant (each a "Warrant" and collectively the "Warrants"); and

         WHEREAS,  the  Company and the  Purchasers  desire to amend each of the
Warrants as set forth herein;

         NOW,  THEREFORE,  IN CONSIDERATION of the mutual covenants contained in
this Agreement,  and for other good and valuable  consideration  the receipt and
adequacy of which are hereby acknowledged, the Company and each Purchaser agrees
to amend each of the Warrants as follows:

         1. The Expiration Date set forth in the first paragraph of each Warrant
shall be extended by six months so that each  Warrant  shall have an  Expiration
Date of five years and 6 months from the date of issuance.

         2. Section 9(e) of each of the Warrants is hereby  amended and restated
as follows:


         "(e) NUMBER OF WARRANT  SHARES.  Simultaneously  with any adjustment to
         the Exercise  Price  pursuant to paragraphs (a) or (b) of this Section,
         the number of Warrant  Shares that may be  purchased  upon  exercise of
         this Warrant shall be increased or decreased  proportionately,  so that
         after such  adjustment the aggregate  Exercise Price payable  hereunder
         for the  increased or decreased  number of Warrant  Shares shall be the
         same as the aggregate  Exercise  Price in effect  immediately  prior to
         such adjustment."

         4. None of the Purchasers has  transferred  any interest in the Warrant
issued to it under the Agreement.  The Company shall as soon as possible, and in
any  event  within  3 days  of the  date  hereof,  issue  to  each  Purchaser  a
replacement warrant reflecting the amendments set forth in this Amendment.

         5.  The  Agreement  and  each  of the  Warrants,  as  amended  by  this
Amendment,  shall  continue  to be and shall  remain in full force and effect in
accordance with their respective terms.



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         6.  This  Amendment  may be  executed  by  facsimile  in any  number of
counterparts, each of which shall be an original, with the same effect as if the
signatures thereto and hereto were upon the same instrument.


         IN WITNESS WHEREOF, the parties hereto have caused this First Amendment
to the Warrants to be duly executed by their respective  authorized  signatories
as of the date first indicated above.

                                      STRATASYS, INC.


                                      By: /s/ S. Scott Crump
                                          ------------------------------------
                                          Name: S. Scott Crump
                                          Title: CEO



                                      MAINFIELD ENTERPRISES, INC.


                                      By: /s/ Avi Vigder
                                          ------------------------------------
                                          Name: Avi Vigder
                                          Title: Authorized Signatory




                                      SMITHFIELD FIDUCIARY LLC


                                      By: /s/ Adam J. Chill
                                          ------------------------------------
                                          Name: Adam J. Chill
                                          Title: Authorized Signatory

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