EXHIBIT 10.23

NONQUALIFIED STOCK OPTION AGREEMENT
BETWEEN KENNETH W. BRIMMER AND
OXBORO MEDICAL INTERNATIONAL, INC.

THIS AGREEMENT is made effective as of the 20th day of April, 1999, between Oxboro Medical International, Inc., a Minnesota corporation (the"Company"), and
Kenneth W. Brimmer (the"Optionee") on the terms and conditions set forth below.

WHEREAS,
the Board of Directors of the Company has decided to permit Nonqualified Stock Options to be granted to certain individuals providing valuable services to the Company, and
any subsidiaries of the Company, to purchase common stock of the Company; and

WHEREAS,
the Company desires the Optionee to secure stock ownership in the Company in order to increase effectiveness and personal interest in the Company;

NOW
THEREFORE, in consideration of the promises and of the covenants and agreements set forth below, it is mutually agreed as follows:





IN
WITNESS WHEREOF, the parties have executed this Agreement on the day and year below written.

Notice of Exercise of Nonqualified Stock Options

Oxboro
Medical International, Inc. 
13828 Lincoln Street NE 
Ham Lake, MN 55304

Ladies
and Gentlemen:

The
undersigned is the holder of a nonqualified stock option (the "Option") to purchase shares of the common stock ("Stock") of Oxboro Medical International, Inc. (the
"Company"), pursuant to the Nonqualified Stock Option Agreement between            and Oxboro Medical International, Inc., effective as of       
     , 1999. The undersigned
hereby irrevocably elects to exercise the Option to purchase            shares of Stock ("Option Shares"). Enclosed herewith is payment for the Option Shares as required under the Agreement.
The undersigned requests that the certificate representing the Option Shares be issued in the name of the undersigned and delivered to the address set forth below within five (5) business days.

In
connection with the issuance of the Option Shares to the undersigned, the undersigned hereby certifies and represents to the Company that the undersigned is acquiring such shares
for the purpose of investment and not with a view toward distribution. The undersigned understands that these securities have not been registered either under any applicable federal law and rules or
applicable state law and rules and that resale will not be permitted under state law unless the securities are first registered or the sale is a transaction exempt from registration under the
applicable state securities law.

The
undersigned further understands that no sale, offer to sell, or transfer of the Option Shares shall be made unless a registration statement under the federal Securities Act of
1933, as amended (the "Act"), with respect to the Option Shares is then in effect or an exemption from the registration requirements of the Act is then in fact applicable to the Option Shares. The
undersigned understands
that a legend reciting this investment restriction shall be placed on any stock certificate that may be issued to the undersigned.

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