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               FIRST AMENDMENT TO NON-QUALIFIED STOCK OPTION AGREEMENT


     This First Amendment to the Oxboro Medical International, Inc. 
Non-Qualified Stock Option Agreement dated August 17, 1995, is made and 
entered into effective as of the  1st day of September, 1998 between Oxboro, 
Medical International, Inc., a Minnesota corporation (the "Company") and 
Larry A. Rasmusson ("Rasmusson").

                                       RECITALS

     WHEREAS, the Company granted a Stock Option to Rasmusson effective 
August 17, 1995 to purchase Eighty Thousand Three Hundred Sixty-Four (80,364) 
shares of Common Stock ("Stock") of the Company at a price of $1.50 per share;

     WHEREAS, on January 14, 1998 there remained Twenty Thousand Three 
Hundred Sixty-Four (20,364) shares of said Stock outstanding under the option;

     WHEREAS, on January 14, 1998 the Company and Rasmusson entered into a 
Stock Option Exercise and Loan Agreement to effect an exercise of the option 
and an acquisition of the Twenty Thousand Three Hundred Sixty-Four (20,364) 
shares in consideration of a Secured Promissory Note in the amount of Thirty 
Thousand Five Hundred Forty-Six and No/100 Dollars($30,546.00), which shares 
were pledged to the Company as security for the Note under an Instruments 
Security Agreement dated January 15, 1998;

     WHEREAS, the Company and Rasmusson desire to effect a rescission to said 
Stock Option Exercise and Loan Agreement, secured Promissory Note and 
Instruments Security Agreement;

     WHEREAS, the Company and Rasmusson desire to reinstate and amend the 
terms of the Non-Qualified Stock Option Agreement as set forth below.

                                 TERMS AND CONDITIONS

     NOW, THEREFORE, in consideration of the mutual promises hereinafter 
contained, the parties hereto agree as follows:

     1.   RESCISSION OF THE STOCK OPTION EXERCISE AND LOAN AGREEMENT, SECURED 
          PROMISSORY NOTE AND INSTRUMENTS SECURITY AGREEMENT.  The Company 
          and Rasmusson hereby rescind in their entirety the Stock Option 
          Exercise and Loan Agreement, Secured Promissory Note and 
          Instruments Security Agreement between the Company and Rasmusson, 
          all dated January 15, 1998.  The Twenty Thousand Three Hundred 
          Sixty-Four (20,364) shares of the Company's Common Stock issued to 
          Rasmusson pursuant to the Certificate of Common Stock of Oxboro 
          Medical International, Inc. No. __ shall be and hereby is returned 
          to the Company duly endorsed by Rasmusson or pursuant to an 
          Assignment Separate from Certificate. Both the Company and 
          Rasmusson are hereby relieved from 

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          any and all obligation, duties and responsibilities under said 
          Stock Option Exercise and Loan Agreement, Secured Promissory Note 
          and Instruments Security Agreement.
     
     2.   TERM OF OPTION.  This Option must be exercised, if at all, and to 
          the extent exercised, on or before March 31, 1999.

     3.   EXERCISE OF OPTION.  This Option may be exercised either by payment 
          in full in cash, by certified or cashier's check or, by the 
          transfer to the Company of shares of Stock already owned by 
          Rasmusson and having a fair market value, as of the date of the 
          exercise of the this Option, which is not less than the purchase 
          price of the Stock being acquired pursuant to the Option provided 
          that such shares of Stock were acquired and full consideration paid 
          therefore at least six (6) months prior to such delivery or by 
          execution of an interest-free Promissory Note by Rasmusson in the 
          amount of Thirty Thousand Five Hundred Forty-Six and No/100 Dollars 
          ($30,546.00) which Note shall be payable in full on or before 
          September 1, 2000.  If the Option is exercised by the execution of 
          a Promissory Note, in the form attached hereto as Exhibit 1, then 
          the Note shall be secured by any and all payments due to Rasmusson 
          by the Company.  If the Note is not paid in full on or before 
          September 1, 2000, then the Company may apply any and all amounts 
          due and owing to Rasmusson at such time to payment of the Note.  
          Further, the shares shall be held as additional collateral for 
          payment of the Note; however, Rasmusson may vote the shares while 
          such shares are being held as collateral by the Company.  Such 
          shares shall be held as collateral pursuant to an Instruments 
          Security Agreement in the form attached hereto as Exhibit 2.  All 
          other terms and conditions of the Option remain unchanged and are 
          in full force and effect.
                                       
                                       OXBORO MEDICAL INTERNATIONAL, INC.
                              
                              
                                       By:  /s/ Robert S. Garin
                                           ---------------------------------
                                           Its:  Chairman of the Board
                                                ----------------------------
     
     
                                       RASMUSSON
     
     
     
                                        /s/ Larry A. Rasmusson              
                                       -------------------------------------
                                       Larry A. Rasmusson


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