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                                                                  Exhibit 3.1

                              AMENDED AND RESTATED

                          CERTIFICATE OF INCORPORATION

                                       OF

                                   SAUER INC.

         SAUER INC., a corporation organized and existing under the laws of the
State of Delaware (the "Corporation"), hereby certifies as follows:

         1. The present name of the corporation is Sauer Inc. Sauer Inc. was
originally incorporated under the name Sundstrand Venture Company, and the
original Certificate of Incorporation was filed with the Secretary of State of
the State of Delaware on September 25, 1986.

         2. This Amended and Restated Certificate of Incorporation amends and
restates the provisions of the Certificate of Incorporation of this Corporation
as heretofore amended or supplemented, and was duly adopted in accordance with
the provisions of Sections 242 and 245 of the General Corporation Law of the
State of Delaware.

         3. The text of the Certificate of Incorporation is hereby amended and
restated to read in its entirety as follows:

         FIRST:  The name of the corporation is Sauer-Danfoss Inc. (hereinafter,
the "Corporation").

         SECOND: Its registered office in the State of Delaware is to be located
at 1209 Orange Street, in the City of Wilmington, County of New Castle, Delaware
19801. The name of its registered agent at such address is The Corporation Trust
Company.

         THIRD: The nature of the business or purposes to be conducted or
promoted is to engage in any lawful act or activity for which corporations may
be organized under the General Corporation Law of Delaware.

         FOURTH: The total number of shares of all classes of stock which the
Corporation shall have authority to issue shall be 79,500,000, of which
75,000,000 shares are to be Common Stock, having a par value of $0.01 per share,
and 4,500,000 shares are to be Preferred Stock, having a par value of $0.01 per
share.

         Authority is hereby expressly granted to the Board of Directors from
time to time to issue Preferred Stock, for such consideration and on such terms
as it may determine, as Preferred Stock of one or more series and in connection
with the creation of any such series to fix by the resolution or resolutions
providing for the issue of shares thereof the designation, powers and

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relative participating, optional, or other special rights of such series, and
the qualifications, limitations, or restrictions thereof. Such authority of
the Board of Directors with respect to each such series shall include, but
not be limited to, the determination of the following:

         (a) the distinctive designation of, and the number of shares
comprising, such series, which number may be (except where otherwise provided
by the Board of Directors in creating such series) increased or decreased
(but not below the number of shares thereof then outstanding) from time to
time by like action of the Board of Directors;

         (b) the dividend rate or amount for such series, the conditions and
dates upon which such dividends shall be payable, the relation which such
dividends bear to the dividends payable on any other class or classes or any
other series of any class or classes of stock, and whether such dividends
shall be cumulative, and if so, from which date or dates for such series;

         (c) whether or not the shares of such series shall be subject to
redemption by the Corporation and the times, prices, and other terms and
conditions of such redemption;

         (d) whether or not the shares of such series shall be subject to the
operation of a sinking fund or purchase fund to be applied to the redemption or
purchase of such shares and if such a fund be established, the amount thereof
and the terms and provisions relative to the application thereof;

         (e) whether or not the shares of such series shall be convertible into
or exchangeable for shares of any other class or classes, or of any other series
of any class or classes, of stock of the Corporation and, if provision be made
for conversion or exchange, the times, prices, rates, adjustments, and other
terms and conditions of such conversion or exchange;

         (f) whether or not the shares of such series shall have voting rights,
in addition to the voting rights provided by law, and if they are to have such
additional voting rights, the extent thereof;

         (g) the rights of the shares of such series in the event of any
liquidation, dissolution, or winding up of the Corporation or upon any
distribution of its assets; and

         (h) any other powers, preferences, and relative, participating,
optional, or other special rights of the shares of such series, and the
qualifications, limitations, or restrictions thereof, to the full extent now or
hereafter permitted by law and not inconsistent with the provisions hereof.

         FIFTH: The number of directors shall be fixed by, or in the manner
provided in, the Bylaws of the Corporation. The classification of the Board of
Directors into three classes is hereby terminated, and any terms of directors
which extend beyond the 2000 annual meeting of stockholders because of such
classification, shall terminate on the date of the 2000 annual meeting of
stockholders. At each annual meeting of stockholders, commencing with the annual

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meeting in 2000, the full Board of Directors shall be elected to hold office
until the next annual meeting of the stockholders and until their successors
shall be elected and shall qualify, subject, however, to prior death,
resignation, retirement, disqualification or removal from office.

         SIXTH: The Board of Directors shall have power to make, and from time
to time alter, amend, or repeal the Bylaws of the Corporation; provided,
however, that (a) the stockholders shall have the paramount power to alter,
amend and repeal the Bylaws or adopt new Bylaws, exercisable by the affirmative
vote of the holders of not less than 80% of the outstanding shares of the
capital stock of the Corporation entitled to vote generally in the election of
directors (considered for this purpose as one class), and (b) if and to the
extent the stockholders exercise such power, the Board of Directors shall not
thereafter suspend, alter, amend or repeal the Bylaws, or portions thereof,
adopted by the stockholders, unless, in adopting such Bylaws, or portions
thereof, the stockholders otherwise provide.

         SEVENTH: A director of the Corporation shall not be personally liable
to the Corporation or its stockholders for monetary damages for breach of
fiduciary duty as a director, except for liability (a) for any breach of the
director's duty of loyalty to the Corporation or its stockholders, (b) for acts
or omissions not in good faith or which involve intentional misconduct or a
knowing violation of law, (c) under the provisions of Section 174 of the
Delaware General Corporation Law and amendments thereto, or (d) for any
transaction from which the director derived an improper personal benefit. If the
Delaware General Corporation Law is amended to authorize corporate action
further eliminating or limiting the personal liability of directors, then the
liability of a director of the Corporation shall be eliminated or limited to the
fullest extent permitted by the Delaware General Corporation Law, as so amended.
No amendment, repeal or adoption of any provision of this Certificate of
Incorporation inconsistent with this Article Seventh shall apply or have any
effect on the liability of any director of the Corporation for or with respect
to any acts or omissions of such director occurring prior to such amendment,
repeal, or adoption of any inconsistent provision.

         EIGHTH: The stockholders of the Corporation may not take action by
written consent in lieu of a meeting, but must take any such action at a duly
called annual or special meeting.

         NINTH:

         (a) Each person who was or is made a party or is threatened to be made
a party to or is involved in any action, suit or proceeding, whether civil,
criminal, administrative or investigative ("proceeding"), by reason of the fact
that he or she, or a person of whom he or she is the legal representative, is or
was a director or officer of the Corporation, or is, or was serving, at the
request of the Corporation as a director or officer of another corporation, or
of a partnership, joint venture, trust or other enterprise, including service
with respect to employee benefit plans, whether the basis of such proceeding is
alleged action in an official capacity as a director or officer or in any other
capacity while serving as a director or officer, shall be indemnified and held
harmless by the Corporation to the fullest extent authorized by the Delaware
General Corporation Law, as the same exists or may hereafter be amended (but, in
the

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case of any such amendment, only to the extent that such amendment permits
the Corporation to provide broader indemnification rights than said laws
permitted the Corporation to provide prior to such amendment), against any
and all expense, liability loss (including attorneys' fees, judgments, fines,
ERISA excise taxes or penalties and amounts paid or to be paid in settlement
and amounts expended in seeking indemnification granted to such person under
applicable law, this Article Ninth or any agreement with the Corporation)
reasonably incurred or suffered by such person in connection therewith and
such indemnification shall continue as to a person who has ceased to be a
director or officer and shall inure to the benefit of his or her heirs,
executors and administrators; provided, however, that, except as provided in
paragraph (b) of this Article Ninth, the Corporation shall indemnify any such
person seeking indemnity in connection with an action, suit or proceeding (or
part thereof) initiated by such person only if (a) such indemnification is
expressly required to be made by law, (b) the action, suit or proceeding (or
part thereof) was authorized by the Board of Directors of the Corporation,
(c) such indemnification is provided by the Corporation, in its sole
discretion, pursuant to the powers vested in the Corporation under the
Delaware General Corporation Law, or (d) the action, suit or proceeding (or
part thereof) is brought to establish or enforce a right to indemnification
under an indemnity agreement or any other statute or law or otherwise as
required under Section 145 of the Delaware General Corporation Law. Such
right shall be a contract right and shall include the right to be paid by the
Corporation expenses incurred in defending any such proceeding in advance of
its final disposition; provided, however, that, unless the Delaware General
Corporation Law then so prohibits, the payment of such expenses incurred by a
director or officer of the Corporation in his or her capacity as a director
or officer (and in any other capacity in which service was or is tendered by
such person while a director or officer, including, without limitation,
service to an employee benefit plan) in advance of the final disposition of
such proceeding shall be made only upon delivery to the Corporation of an
undertaking, by or on behalf of such director of officer, to repay any
amounts so advanced if it should be determined ultimately that such director
or officer is not entitled to be indemnified under this Article Ninth or
otherwise.

         (b) If a claim under paragraph (a) of this Article Ninth is not paid
in full by the Corporation within thirty (30) days after a written claim has
been received by the Corporation, the claimant may at any time thereafter
bring suit against the Corporation to recover the unpaid amount of the claim
and, if such suit is not frivolous or brought in bad faith, the claimant
shall be entitled to be paid also the expense of prosecuting such claim. The
burden of proving such claim shall be on the claimant. It shall be a defense
to any such action (other than an action brought to enforce a claim for
expenses incurred in defending any proceeding in advance of its final
disposition where the required undertaking, if any, has been tendered to this
Corporation) that the claimant has not met the standards of conduct which
make it permissible under the Delaware General Corporation Law for the
Corporation to indemnify the claimant for the amount claimed. Neither the
failure of the Corporation (including its Board of Directors, independent
legal counsel, or its stockholders) to have made a determination prior to the
commencement of such action that indemnification of the claimant is proper in
the circumstances because he or she has met the applicable standard of
conduct set forth in the Delaware General Corporation Law, nor an actual
determination by the Corporation (including its Board of Directors,
independent legal

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counsel or its stockholders) that the claimant has not met such applicable
standard of conduct, shall be a defense to the action or create a presumption
that claimant has not met the applicable standard of conduct.

         (c) The rights conferred on any person in paragraphs (a) and (b) of
this Article Ninth shall not be exclusive of any other right which such persons
may have or hereafter acquire under any statute, provision of this Certificate
of Incorporation, the Bylaws of the Corporation, agreement, vote of stockholders
or disinterested directors or otherwise.

         (d) The Board of Directors is authorized to enter into a contract with
any director, officer, employee or agent of the Corporation, or any person
serving at the request of the Corporation as a director, officer, employee or
agent of another corporation, partnership, joint venture, trust or other
enterprise, including employee benefit plans, providing for indemnification
rights equivalent to or, if the Board of Directors so determines, greater than,
those provided for in this Article Ninth.

         (e) The Corporation may maintain insurance to the extent reasonably
available, at its expense, to protect itself and any such director, officer,
employee or agent of the Corporation or another corporation, partnership, joint
venture, trust or other enterprise against any such expense, liability or loss,
whether or not the Corporation would have the power to indemnify such person
against such expense, liability or loss under the Delaware General Corporation
Law.

         (f) Any amendment, repeal or modification of any provision of this
Article Ninth by the stockholders or the directors of the Corporation shall not
adversely affect any right or protection of a director or officer of the
Corporation existing at the time of such amendment, repeal or modification.

         TENTH: Notwithstanding any other provision of this Certificate of
Incorporation or the Bylaws of the Corporation (and in addition to any other
vote that may be required by law, this Certificate of Incorporation, or the
Bylaws of the Corporation), the affirmative vote of the holders of not less than
80% of the outstanding shares of the capital stock of the Corporation entitled
to vote generally in the election of directors (considered for this purpose as
one class) shall be required to amend, alter, or repeal any provision of this
Article Tenth or Articles Fifth, Sixth, Seventh, Eighth, and Ninth of this
Certificate of Incorporation.

         IN WITNESS WHEREOF, this Amended and Restated Certificate of
Incorporation has been executed on behalf of the Corporation this ____ day of
__________________, 2000.

                            SAUER INC.

                            By:
                               -----------------------------------------------
                               David J. Anderson, Vice President

ATTEST:
       -----------------------------------------
             Kenneth D. McCuskey, Secretary


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STATE OF IOWA              )
                           )ss.
COUNTY OF STORY            )

         BE IT REMEMBERED that on this ____ day of _________________, 2000,
personally came before me, David J. Anderson, to me personally known to be the
same person who executed the foregoing Certificate, and acknowledged that he
signed as his free act and deed the foregoing document and declared that the
statements therein contained are true to his best knowledge and belief.

         IN WITNESS WHEREOF, I have hereunto set my hand and seal the day and
year above written.

                                                   ---------------------------
                                                    Notary Public

My commission expires:

---------------------

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