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                                                                     EXHIBIT 3.1

 
                AMENDED AND RESTATED CERTIFICATE OF INCORPORATION
                                       OF
                          UNITED RENTALS HOLDINGS, INC.

            United Rentals Holdings, Inc., a corporation organized and existing
under the laws of the State of Delaware (the "Corporation"), hereby certifies as
follows:

            1. The name of the corporation is United Rentals Holdings, Inc. The
original Certificate of Incorporation (the "Original Certificate") of the
Corporation was filed with the Secretary of State of the State of Delaware on
July 20, 1998.

            2. Pursuant to Sections 242 and 245 of the Delaware General
Corporation Law, this Amended and Restated Certificate of Incorporation restates
and integrates and further amends the provisions of the Corporation's
Certificate of Incorporation.

            3. The terms and provisions of this Amended and Restated Certificate
of Incorporation have been duly adopted pursuant to the provisions of Sections
242 and 245 of the Delaware General Corporation Law.

            4. The text of the Original Certificate is hereby restated and
further amended to read in its entirety as follows:

                                   ARTICLE I.

            The name of the Corporation is United Rentals, Inc.

                                   ARTICLE II.

            The address of the Corporation's registered office in the State of
Delaware is United Corporate Services, Inc., 15 East North Street, Dover,
Delaware 19901, County of Kent. The name of its registered agent at such address
is United Corporate Services, Inc.

                                  ARTICLE III.

            A. The Corporation is authorized to issue two classes of stock to be
designated, respectively, "Common Stock" and 
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"Preferred Stock". The amount of the total authorized capital stock of the
Corporation is 80,000,000 shares, divided into (a) 75,000,000 shares of Common
Stock having a par value of $0.01 per share, and (b) 5,000,000 shares of
Preferred Stock having a par value of $0.01 per share.

            B. The Preferred Stock may be issued from time to time in one or
more series. Subject to the restrictions prescribed by law, the Board of
Directors is authorized to fix by resolution or resolutions the number of shares
of any series of Preferred Stock and to determine or alter the rights,
preferences, privileges and restrictions granted to or imposed upon any wholly
unissued series of Preferred Stock and, within the limits and restrictions
stated in any resolution or resolutions of the Board of Directors originally
fixing the number of shares constituting any series of Preferred Stock, to
increase (but not above the total number of authorized shares of Preferred
Stock) or decrease (but not below the number of shares of any such series then
outstanding) the number of shares of any such series subsequent to the issue of
shares of that series.

            The authority of the Board of Directors with respect to each series
of Preferred Stock shall include, but not be limited to, determination of the
following: (a) the number of shares constituting that series and the distinctive
designation of that series; (b) the dividend rate on the shares of that series,
whether dividends shall be cumulative, and if so, from which date or dates, and
the relative rights of priority, if any, of payment of dividends on shares of
that series; (c) whether that series shall have voting rights in addition to the
voting rights provided by law, and if so, the terms of such voting rights; (d)
whether that series shall have conversion privileges, and if so, the terms and
conditions of such privileges, including provision for adjustment of the
conversion rate in such events as the Board of Directors shall determine; (e)
whether or not the shares of that series shall be redeemable, and if so, the
terms and conditions of such redemption, including the date or dates upon or
after which they shall be redeemable, and the amount per share payable in case
of redemption, which amount may vary under different conditions and at different
redemption dates; (f) whether that series shall have a sinking fund for the
redemption or purchase of shares of that series, and if so, the terms and the
amount of such sinking funds; (g) the rights of the shares of that series in the
event of voluntary or involuntary 

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liquidation, dissolution or winding up of the Corporation, and the relative
rights of priority, if any, of payment of shares of that series; and (h) any
other relative rights, preferences and limitations of that series.

                                   ARTICLE IV.

            The purpose of the Corporation is to engage in any lawful act or
activity for which corporations may now or hereafter be organized under the
Delaware General Corporation Law.

                                   ARTICLE V.

            A. By-Laws. In furtherance and not in limitation of the powers
conferred by statute, the Board of Directors is expressly authorized to make,
adopt, alter, amend or repeal the By-Laws of the Corporation. Any By-Laws made
by the directors under the powers conferred hereby may be amended or repealed by
the directors or by the stockholders. Notwithstanding the foregoing and anything
contained in this Amended and Restated Certificate of Incorporation to the
contrary, the By-Laws shall not be amended or repealed by the stockholders, and
no provision inconsistent therewith shall be adopted by the stockholders,
without the affirmative vote of the holders of at least 66-2/3% of the voting
power of all shares of the Corporation entitled to vote generally in the
election of directors, voting together as a single class.

               B. Amendment of Certificate of Incorporation. Notwithstanding any
other provision contained in this Amended and Restated Certificate of
Incorporation and notwithstanding that a lesser percentage may be specified by
law, the By-Laws or otherwise, this Article V and Articles VI, VII, VIII and IX
of this Amended and Restated Certificate of Incorporation shall not be amended
or repealed, and no provision inconsistent therewith or providing for cumulative
voting in the election of directors shall be adopted, unless such adoption,
amendment or repeal is approved by the affirmative vote of holders of at least
66-2/3% of the voting power of all shares of capital stock of the Corporation
entitled to vote generally for the election of directors.


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                                   ARTICLE VI.

            The business and affairs of the Corporation shall be managed by and
under the direction of the Board of Directors (the "Board"). The Board may
exercise all such authority and powers of the Corporation and do all such lawful
acts and things as are not by statute or this Amended and Restated Certificate
of Incorporation directed or required to be exercised or done by the
stockholders.

            A. Number of Directors. The number of directors comprising the
entire Board shall, subject to the right, if any, of holders of Preferred Stock
to elect directors under specified circumstances, be such number as may be fixed
from time to time exclusively by the Board by action of a majority of the
directors then in office. If the number of directors at any time is fixed at
three or greater, then thereafter in no event shall such number be fewer than
three or greater than nine, unless approved by action of not less than
two-thirds of the directors then in office. No director need be a stockholder.

            B. Classes and Terms of Directors. The directors shall be divided
into three classes (I, II and III). The number of directors comprising each
class (assuming no vacancy in any class) shall be as nearly equal in number as
possible based upon the number of directors comprising the entire Board. The
Board shall, at or before the first meeting of the Board following the Effective
Time (as that term is defined in the document titled "Amended and Restated
Certificate of Incorporation of United System, Inc." filed with the Delaware
Secretary of State on September 11, 1997), designate the class to which each
director then serving shall be a member. The initial term of the directors in
Class I shall extend until the first annual meeting of stockholders following
the Effective Time; the initial term of the directors in Class II shall extend
until the second annual meeting of stockholders following the Effective Time;
and the initial term of the directors in Class III shall extend until the third
annual meeting of stockholders following the Effective Time. At each annual
meeting of stockholders, successors to directors of the class whose term expires
at such meeting will be elected to serve for three-year terms and until their
successors are elected and qualified.


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            C. Newly-Created Directorships and Vacancies. Subject to the rights
of the holders of any class or series of Preferred Stock then outstanding, newly
created directorships resulting from any increase in the number of directors or
any vacancies in the Board resulting from death, resignation, retirement,
disqualification, removal from office or any other cause may be filled by the
Board (and not by the stockholders unless there are no directors then in
office), provided that a quorum is then in office and present, or by a majority
of the directors then in office, if less than a quorum is then in office, or by
the sole remaining director. A director elected to fill a newly created
directorship or other vacancy shall hold office for the remainder of the full
term of the class of directors in which the new directorship was created or the
vacancy occurred and until such director's successor has been elected and
qualified.

            D. Removal of Directors. Subject to the rights of the holders of any
class or series of Preferred Stock then outstanding, the directors or any
director may be removed from office any time, but only for cause, at a meeting
called for that purpose, and only by the affirmative vote of the holders of at
least 66-2/3% of the voting power of all shares of the Corporation entitled to
vote generally in the election of directors, voting together as a single class.

            E. Rights of Holders of Preferred Stock. Notwithstanding the
foregoing provisions of this Article VI, whenever the holders of any one or more
classes or series of Preferred Stock issued by the Corporation shall have the
right, voting separately by class or series, to elect directors at an annual or
special meeting of stockholders, the election, term of office, filling of
vacancies and other features of such directorships shall be governed by the
rights and preferences of such Preferred Stock, and such directors so elected
shall not be divided into classes pursuant to this Article VI unless expressly
provided by such rights and preferences.

            F. Written Ballot Not Required. The election of directors need not
be by written ballot unless the By-Laws of the Corporation shall so provide.


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                                  ARTICLE VII.

            The By-Laws of the Corporation may provide, without limitation,
requirements relating to the notice and conduct of annual meetings, special
meetings, and the nomination and election of directors of the Corporation.

                                  ARTICLE VIII.

            In furtherance and not in limitation of the powers conferred by law
or in this Amended and Restated Certificate of Incorporation, the Board (and any
committee of the Board) is expressly authorized, to the extent permitted by law,
to take such action or actions as the Board or such committee may determine to
be reasonably necessary or desirable to (a) encourage any person to enter into
negotiations with the Board and management of the Corporation with respect to
any transaction which may result in a change in control of the Corporation which
is proposed or initiated by such person or (b) contest or oppose any such
transaction which the Board or such committee determines to be unfair, abusive
or otherwise undesirable with respect to the Corporation and its business,
assets or properties or the stockholders of the Corporation, including, without
limitation, the adoption of plans or the issuance of rights, options, capital
stock, notes, debentures or other evidences of indebtedness or other securities
of the Corporation, which rights, options, capital stock, notes, evidences of
indebtedness and other securities (i) may be exchangeable for or convertible
into cash or other securities on such terms and conditions as may be determined
by the Board or such committee and (ii) may provide that any holder or class of
holders thereof designated by the Board or any such committee will be treated
differently than all other holders in respect of the terms, conditions,
provisions and rights of such securities.

                                   ARTICLE IX.

            Subject to the rights, if any, of holders of any class or series of
Preferred Stock then outstanding, (i) stockholders are not permitted to call a
special meeting of stockholders or to require the Board or officers of the
Corporation to call such a special meeting, (ii) a special meeting of
stockholders may only be called by a majority of the Board or by the chief
executive officer, (iii) the business permitted to be conducted at a 


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special meeting of stockholders shall be limited to matters properly brought
before the meeting by or at the direction of the Board, and (iv) any action
required or permitted to be taken by the stockholders must be taken at a duly
called and convened annual meeting or special meeting of stockholders and cannot
be taken by consent in writing.

            Meetings of stockholders may be held within or without the State of
Delaware, as the By-Laws may provide. The books of the Corporation may be kept
(subject to any provision contained in the statute) outside the State of
Delaware at such place or places as may be designated from time to time by the
Board or in the By-Laws of the Corporation.

                                   ARTICLE X.

            A director of the Corporation shall not be personally liable to the
Corporation or its stockholders for monetary damages for any breach of fiduciary
duty as a director, except for liability (i) for any breach of the director's
duty of loyalty to the Corporation or its stockholders, (ii) for acts or
omissions not in good faith or which involve intentional misconduct or a knowing
violation of law, (iii) under Section 174 of the Delaware General Corporation
Law, or (iv) for any transaction from which the director derived an improper
personal benefit. If the Delaware General Corporation Law is amended after
approval by the stockholders of this Article to authorize corporate action
further eliminating or limiting the personal liability of directors, then the
liability of a director shall be eliminated or limited to the fullest extent
permitted by the Delaware General Corporation Law, as so amended.

            IN WITNESS WHEREOF, the Corporation has caused this Amended and
Restated Certificate of Incorporation to be duly executed this 5th day of
August, 1998.

                                    United Rentals Holdings, Inc.


                                    By: /s/ Sandra E. Welwood
                                        --------------------------------
                                        Name: Sandra E. Welwood
                                        Title: Vice President


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