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                                                                     Exhibit 4.3

                               SECOND AMENDMENT TO

                                    WARRANTS



         This Second  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  a Warrant,  as  amended by First  Amendment  to  Warrants,  dated and
effective as of August 22, 2003 (each, as amended,  a "Warrant" and collectively
the "Warrants"); and

         WHEREAS, the Company and the Purchasers desire to further 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. Section 11(b) of each of the Warrants is hereby amended and restated
as follows:

                  (b) Notwithstanding anything to the contrary contained herein,
         the maximum  number of shares of Common Stock that the Company shall be
         required to issue pursuant to the Transaction  Documents equals 805,000
         shares,  as  adjusted  for any stock  split,  subdivision,  dividend or
         distribution  payable in shares of Common Stock (or other securities or
         rights  convertible  into, or entitling  the holder  thereof to receive
         directly or indirectly  shares of Common  Stock),  reverse stock split,
         combination or other similar  recapitalization or event occurring after
         August 17, 2003 (the  "Issuable  Maximum").  If, at the time any Holder
         requests an exercise of any of the Warrants, the Actual Minimum exceeds
         the  Issuable  Maximum,  then the  Company  shall  issue to the  Holder
         requesting  such  exercise or  conversion  a number of shares of Common
         Stock not  exceeding  such  Holder's  pro-rata  portion of the Issuable
         Maximum (based on such Holder's share  (vis-a-vis other Holders) of the
         aggregate  purchase price paid under the Purchase  Agreement and taking
         into account any Underlying  Shares  previously issued to such Holder),
         this Warrant  shall  terminate  with  respect to such  Holder,  and the
         Company  shall have no further  obligations  to issue  shares of Common
         Stock or otherwise under this Warrant. For the purposes hereof, "Actual
         Minimum"  shall mean, as of any date, the maximum  aggregate  number of
         shares of Common  Stock


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         then  issued or  potentially  issuable  in the future  pursuant  to the
         Transaction  Documents,  including any Underlying  Shares issuable upon
         exercise in full of all Warrants,  without  giving effect to any limits
         on the  number of shares of Common  Stock that may be owned by a Holder
         at any one time.


         3. 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 amendment set forth in this Amendment.

         4.  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.

         5.  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  Second
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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