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                         OXBORO MEDICAL INTERNATIONAL, INC.
                        NONQUALIFIED STOCK OPTION AGREEMENT
                                          
                                   March 20, 1998

Dear Mr. Sayer:

     At the direction of the Board of Directors of Oxboro Medical 
International, Inc. (the "Company"), you are hereby notified that the Board 
has granted to you a Stock Option ("Option") to purchase 40,000 shares of 
Common Stock ("Stock") of the Company at a price of $2.00 per share.  The 
date of grant of this Option is the date of this notice, and it is the 
determination of the Board of Directors that on this date the fair market 
value of the Company's Common Stock does not exceed $2.00  per share.

     You are not required to exercise this Option.  This Option must be 
exercised, if at all and to the extent exercised, on or before March 21, 2003.

     Your Option is in all respects limited and conditioned by the following:

     a.   Your Option is immediately exercisable in full.

     b.   The purchase price of any Stock purchased pursuant to exercise of 
this Option may be paid in cash or by certified or cashier's check or by 
delivery to the Company of shares of Stock owned by you for at least six 
months prior to delivery in an amount equal in fair market value to the 
purchase price of the shares of Stock being purchased pursuant to this 
Option.  In addition, such purchase price may be paid by a loan from the 
Company upon such terms as the Board of Directors may establish from time to 
time.

     c.   Your Option may be exercised by you, but only by you, at any time 
during your lifetime prior to six (6) months after the date of the 
termination of your service as a member of the Board of Directors of the 
Company, but only to the extent you were entitled to exercise your Option at 
the date of such termination and only if your Option has not expired.  In no 
event will your Option be exercisable after the expiration of five (5) years 
from the date such Option is granted.

     d.   In the event of your death while you are a director of the Company, 
your Option may be exercised at any time within six (6) months following the 
date of your death by your estate or by a person who acquired the right to 
exercise your Option by will or the laws of descent and distribution.  In 
either case, such Option may be exercised only to the extent you were 
entitled to exercise the Option at the time of your death.  In the event of 
your death within ninety (90) days after termination of your service as a 
director, then the Option may be exercised at any time within three (3) 
months following the date of your death by your estate or by a person who 
acquired the right to exercise your Option by will or by the laws of descent 
and distribution, but only to the extent you were entitled to exercise the 
Option at the time of such termination.

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     e.   You may not transfer, sell, pledge, assign, or otherwise dispose of 
your Option, other than at death by will or the laws of descent and 
distribution, and your Option during your lifetime is exercisable only by you.

     f.   The shares of Stock you may acquire upon exercise of your Option 
are subject to restrictions against transfer.

     g.   Unless a registration statement under the Securities Act of 1933 
(and applicable state securities laws) is in effect with respect to this 
Option or Stock to be purchased pursuant to this Option, you agree with, and 
represent to, the Company that you are acquiring the Option and Stock for the 
purpose of investment and not with a view to transfer, sell, or otherwise 
dispose of the Option or Stock, except as may be permitted under applicable 
securities laws. The Company may require an opinion of counsel satisfactory 
to it prior to the transfer of any Stock to or by you to assure at all times 
that such transaction will be in compliance with applicable federal and state 
securities laws.

     As a condition to the issuance of shares of Stock under this Option, you 
agree to remit to the Company at the time of any exercise of this Option any 
taxes required to be withheld by the Company under federal, state, or local 
law as a result of your exercise of this Option.  At your option, such taxes 
may be paid by delivery to the Company of shares of Stock already owned by 
you or withholding of shares issuable upon exercise of this Option, in either 
case in an amount equal in fair market value to the taxes owed.
     
     
                                       OXBORO MEDICAL INTERNATIONAL, INC.
     
     
                                       By   /s/ Larry A. Rasmusson  
                                            ----------------------------------
                                            Larry A. Rasmusson
                                            Its Chief Executive Officer



                                     ACCEPTANCE

     I hereby accept the terms and provisions of the above Nonqualified Stock 
Option Agreement and agree to be bound by its terms.  I also agree to accept 
as binding, conclusive, and final all decisions or interpretations of the 
Company's Board of Directors upon any questions arising under the Option.

Dated effective Feb. 20, 1998.
                -------


                                       /s/ John Sayer
                                       ---------------------------------------
                                       John Sayer


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                         NOTICE OF EXERCISE OF STOCK OPTION
                            AND RECORD OF STOCK TRANSFER

     I hereby exercise the Stock Option granted by Oxboro Medical 
International, Inc., effective  March 20, 1998, subject to all terms and 
provisions thereof, and notify you of my desire to purchase _______ shares of 
Common Stock of the Company (the "Shares"), offered to me pursuant to said  
Option.  Enclosed is my check in the sum of $_________________ in full 
payment for the Shares.

     [This paragraph is applicable if the Shares are not registered under the
Securities Act of 1933.]  I hereby represent that the Shares are being acquired
by me as an investment and not with a view to, or for resale in connection 
with, the distribution of any shares of the Company.  I understand that the 
Shares are not registered under the Securities Act of 1933, as amended (the 
"Act"), or applicable state securities laws, that the Shares may not be sold 
or otherwise transferred except pursuant to an effective registration 
statement under the Act and said laws unless the Company has received an 
opinion of counsel satisfactory to it that such transfer or disposition does 
not require registration under the Act or said laws and, for any sales under 
Rule 144 of the Act, such evidence as it shall request for compliance with 
that rule or applicable state securities laws, and that the certificate 
representing the Shares may contain a legend referring to such restrictions.

     I agree that I am responsible for any taxes payable as a result of the 
exercise of the option or the sale of the shares issued upon such exercise.  
I agree that if the Company is required to withhold any taxes as a result of 
my exercise of the option, I will remit any required amount to the Company as 
a condition to the issuance to me of the Shares.


Dated: _______________, 19__.

                                       ________________________________________
                                       Optionee's Signature


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                                      RECEIPT


     RECEIPT is hereby acknowledged of the delivery to me by Oxboro Medical 
International, Inc., on ____________, 19__, of stock certificate no. 
____________ for _________ shares of Common Stock purchased by me pursuant to 
the terms and conditions of a stock option granted to me effective March 20, 
1998.

                                       ________________________________________
                                       Optionee


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