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Exhibit 3.1

COMPOSITE
ARTICLES OF INCORPORATION
OF
OXBORO MEDICAL, INC.

ARTICLE I

The name of this corporation shall be Oxboro Medical, Inc.

ARTICLE II

This corporation has been formed for general business purposes.

ARTICLE III

The corporation shall have all of the powers granted or available under the laws of the state of Minnesota and laws amendatory thereof and supplementary
thereto, including but not limited to the following:



ARTICLE IV

The duration of this corporation shall be perpetual.

ARTICLE V

The location and post office address of this corporation's registered office in this state shall be 13828 Lincoln Street, N. E., Ham Lake, Minnesota
55304.



ARTICLE VI

The minimum amount of stated capital with which this corporation will begin business shall not be less than One Thousand and no/100 Dollars ($1,000.00).

ARTICLE VII



ARTICLE VIII

The name and post office address of the incorporator of this corporation are as follows:

Steven
R. Hedges
2850 Metro Drive, Suite 800
Minneapolis, MN 55420

ARTICLE IX

The business and affairs of this corporation shall be managed by or under the direction of a Board of Directors consisting of not less than two persons, who
need not be shareholders. The number of directors may be increased by the shareholders or by a 2/3 vote of the entire Board of Directors or decreased by the shareholders to not less
than three; provided, however, that any change in the number
of directors on the Board of Directors (including, without limitation, changes at annual meetings of shareholders) shall be approved by the affirmative vote of not less than 662/3% of
the voting power of this corporation's shares outstanding and entitled to vote, voting together as a single class, unless such change shall have been approved by a majority of the entire Board of
Directors. If such change shall not have been so approved, the number of directors shall remain the same. For purposes of this Article IX, the shares of this corporation entitled to vote shall
be those shares of this corporation's capital stock entitled to vote generally in the election of directors of this corporation.

The
directors shall be divided into three classes, designated Class I, Class II, and Class III, except as otherwise provided pursuant to this Article IX.
Each class shall consist, as nearly as may be possible, of one-third of the total number of directors constituting the entire Board of Directors. At the 1990 annual

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meeting
of shareholders two directors shall be elected, one of whom shall be a Class I director elected for a one-year term and one of whom shall be a Class III director
elected for a three-year term. Any Class II director elected by the shareholders or appointed by the Board of Directors prior to the 1992 annual meeting of shareholders shall serve
until the 1992 annual meeting of shareholders. At each succeeding annual meeting of shareholders beginning in 1991, successors to the class of directors whose term expires at that annual meeting shall
be elected for a three-year term. If the number of directors is changed, any increase or decrease shall be apportioned among the classes so as to maintain the number of directors in each
class as nearly equal as possible, and any additional director of any class elected or appointed to fill a vacancy resulting from an increase in such class shall hold office initially for a term that
shall coincide with the remaining term of that class. In no case will a decrease in the number of directors shorten the term of any incumbent director. A director shall hold office until the annual
meeting for the year in which the director's term expires and until a successor shall be elected and qualify, subject, however, to prior death, resignation, retirement, disqualification or removal
from office. Removal of a director from office by the shareholders, with or without cause, shall require the affirmative vote of the greater of (1) a majority of the voting power of this corporation's
shares outstanding and entitled to vote, voting together as a single class, or (2) at least 662/3% of the voting power of this corporation's shares present and entitled to vote, voting
as a single class. Any vacancy on the Board of Directors that results from an increase in the number of directors shall be filled by a majority of the entire Board of Directors then in office, and any
other vacancy occurring in the Board of Directors shall be filled by a majority of the directors then in office, although less than a quorum, or by a sole remaining director. Any director elected or
appointed to fill a vacancy not resulting from an increase in the number of directors shall have the same remaining term as such director's predecessor. In addition to the authority of the
shareholders to remove directors as described above, any director appointed by the Board of Directors to fill a vacancy, however created, may be removed prior to such director's initial election by
the shareholders, with or without cause, by the vote of a majority of the other members of the Board of Directors then in office.

Notwithstanding
the foregoing, whenever the holders of any one or more classes of capital stock (other than common stock) issued by this corporation shall have the right, voting
separately by class or series, to elect directors at an annual or special meeting of shareholders, the election, term of office, filling of vacancies and other features of such directorships shall be
governed by or pursuant to the applicable terms of the certificate of designation or other instrument creating such class or series of capital stock, and such directors so elected shall not be divided
into classes pursuant to this Article IX unless expressly provided by such terms.

Only
persons who are nominated in accordance with the procedures set forth in this Article IX shall be eligible for election as Directors. Nominations of persons for election
to the Board of Directors of this corporation may be made at a meeting of shareholders (a) by or at the direction of the Board of Directors or (b) by any shareholder of this corporation
entitled to vote for the election of Directors at
the meeting who complies with the notice procedures set forth in this Article IX. Nominations by shareholders shall be made pursuant to timely notice in writing to the Secretary of this
corporation. To be timely, a shareholder's notice shall be delivered to or mailed and received at the principal executive offices of this corporation not less than 50 days prior to the meeting;
provided, however, that in the event that less than 60 days' notice or prior public disclosure of the date of the meeting is given or made to shareholders, notice by the shareholder to be
timely must be so received not later than the close of business on the 10th day following the day on which such notice of the date of the meeting was mailed or such public disclosure was made. Such
shareholder's notice shall set forth (a) as to each person whom the shareholder proposes to nominate for election or re-election as a director, all information relating to such person that is
required (or would be required if this corporation were subject to Regulation 14A under the Securities Exchange Act of 1934, as amended) to be disclosed in solicitations of proxies or otherwise
pursuant to Regulation 14A under the Securities Exchange Act of 1934, as amended (including such person's written consent to being named in the proxy statement as a nominee and to serving as a
director if elected); and (b) as to the shareholder giving the notice (i) the name and address, as they appear on the corporation's books, of such shareholder

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and
(ii) the class and number of shares of this corporation which are beneficially owned by such shareholder. At the request of the Board of Directors any person nominated by the Board of
Directors for election as a director shall furnish to the Secretary of this corporation that information required to be set forth in a shareholder's notice of nomination which pertains to the nominee.
No person shall be eligible for election as a director of this corporation unless nominated in accordance with the procedures set forth in this Article IX. The Chairman of the meeting shall, if
the facts warrant, determine that a nomination was not made in accordance with the procedures prescribed in this Article IX and, if he should so determine, he shall so declare to the meeting
and the defective nomination shall be disregarded.

At
any regular or special meeting of the shareholders, only such business shall be conducted as shall have been brought before the meeting (a) by or at the direction of the
Board of Directors or (b) by any shareholder of this corporation who complies with the notice procedures set forth in this Article IX. For business to be properly brought before any
regular or special meeting by a shareholder, the shareholder must have given timely notice thereof in writing to the Secretary of this corporation. To be timely, a shareholder's notice must be
delivered to or mailed and received at the principal executive offices of the corporation not less than 50 days prior to the meeting, provided, however, that in the event that less than
60 days' notice or prior public disclosure of the date of the meeting is given or made to the shareholders, notice by the shareholder to be timely must be received not later than the close of
business on the 10th day following the day on which such notice of the date of the regular or special meeting was mailed or such public disclosure was made. A shareholder's notice to the Secretary
shall set forth as to each matter the shareholder proposes to bring before the regular or special meeting (a) a brief description of the business desired to be brought before the meeting and the
reasons for conducting such business at the meeting, (b) the name and address, as they appear on this corporation's books, of the shareholder proposing such business, (c) the class and number of
shares of this corporation which are beneficially owned by the shareholder and (d) any material interest of the shareholder in such business. Notwithstanding anything in this corporation's Bylaws to
the contrary, no business shall be conducted at any regular or special meeting except in accordance with the procedures set forth in this Article IX. The Chairman of the meeting shall, if the facts
warrant, determine that business was not properly brought before the meeting in accordance with the provisions of this Article IX and, if he should so determine, he shall so declare to the meeting and
any such business not properly brought before the meeting shall not be transacted.

Notwithstanding
any other provisions of these Articles of Incorporation (and notwithstanding the fact that a lesser percentage or separate class vote may be specified by law or these
Articles of
Incorporation), the affirmative vote of the holders of the greater of (1) a majority of the voting power of this corporation's shares outstanding and entitled to vote or (2) at least
662/3% of the voting power of this corporation's shares present and entitled to vote, in each case voting together as a single class, shall be required to amend or repeal, or adopt any
provisions inconsistent with, this Article IX.

ARTICLE X

The authority to make and alter the Bylaws of this corporation is hereby vested in the Board of Directors of this corporation is hereby vested in the Board of
Directors of this corporation to the full extent permitted by law, subject, however, to the power of the shareholders of this corporation to repeal or alter such Bylaws.

Authority
is hereby conferred upon and vested in the Board of Directors of this corporation to accept or reject subscriptions for shares of its capital stock, whether such
subscriptions be made before or after its incorporation. The Board of Directors shall have the authority to issue shares of stock and securities of this corporation to the full amount authorized by
these Articles of Incorporation, and shall have the authority to grant and issue rights to convert securities of the corporation into shares of stock of the corporation, options to purchase shares or
securities convertible into shares, warrants, and other such rights or options, and to fix the terms, provisions and conditions of such rights, options and warrants, including the option

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price
or prices at which shares may be purchased or subscribed for and the conversion basis or bases of such rights, options and warrants.

ARTICLE XI

The shareholders of this corporation may, by a majority vote of all shares issued, outstanding and entitled to vote:



ARTICLE XII

The shareholders of this corporation expressly elect not to be subject to the provisions of the Minnesota Business Combination Act, Section 302A.673 of
the Minnesota Statutes, as currently in effect and as may be amended from time to time. This Article XII, as amended, shall become effective 18 months from the date of shareholder
approval of this amendment on March 16, 2000, and except as otherwise provided in Section 302A.673, Subdivision 3(c) of the Minnesota Statutes, this election shall not apply to
any business combination of the corporation with an interested shareholder whose share acquisition date is on or before the effective date of this amendment.

ARTICLE XIII

The shareholders of this corporation expressly elect not to be subject to the provisions of the Control Share Acquisition Statute, Section 302A.671, et.
seq., of the Minnesota Statutes.

ARTICLE XIV

To the fullest extent permitted by the Minnesota Business Corporation Act as the same exists or may hereafter be amended, a director of this corporation shall
not be liable to this corporation or its stockholders for monetary damages for breach of fiduciary duty as a director.

ARTICLE XV

In accordance with Section 302A.239, Subdivision 1 of the Minnesota Statutes, any actions taken by written consent of the Board of Directors of
this corporation, other than an action requiring shareholder approval, shall be effective if signed either by all of the directors or by the number of directors that would be required to take the same
action at a meeting of the board at which all directors were present.

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