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                                                                       EXHIBIT 4

                              AMENDED AND RESTATED
                                VOTING AGREEMENT

This Amended and Restated to Voting Agreement is made and entered into as of
March 31, 2004 by and between Cooper Industries, Ltd., a Bermuda corporation
("Cooper Bermuda"), Cooper Industries, Inc., an Ohio corporation ("Cooper
Ohio"), and Cooper Bermuda Investments, Ltd., a Bermuda corporation ("CBI")
(Cooper Ohio and CBI each an "Affiliated Shareholder") and amends the Voting
Agreement entered into as of May 21, 2002 by and between Cooper Bermuda and
Cooper Ohio.

WHEREAS, Cooper Ohio and Cooper Bermuda entered into a series of transactions on
May 22, 2002 ("Reorganization"), whereby Cooper Ohio transferred certain assets
to Cooper Bermuda in exchange for shares of Class B common stock of Cooper
Bermuda, and Cooper Ohio became a wholly-owned subsidiary of Cooper Bermuda; and

WHEREAS, Cooper Ohio entered into the Voting Agreement to ensure that the rights
of its shareholders, which became shareholders of Cooper Bermuda in the
Reorganization, would not be adversely effected through Cooper Ohio's ownership
of Cooper Bermuda stock; and

WHEREAS, it is in the interest of the parties hereto that CBI, a wholly-owned
indirect subsidiary of Cooper Ohio, may purchase Class A common shares of Cooper
Bermuda stock on the open market in lieu of the purchase of such shares by
Cooper Ohio or Cooper Bermuda; and

WHEREAS, the parties hereto desire to ensure that the rights of Cooper Bermuda
shareholders are not adversely affected by the purchase and ownership of Cooper
Bermuda stock by CBI.

NOW THEREFORE, in consideration of the mutual agreements contained herein and
other good and adequate consideration, the parties agree as follows:

                               I. Representations

Cooper Bermuda and each Affiliated Shareholder represents and warrants to the
others that:

      a.    it has the requisite power and authority to enter into and perform
            this Agreement;

      b.    its execution, delivery and performance of this Agreement have been
            duly authorized by all necessary corporate action;

      c.    this Agreement has been duly executed by an authorized officer of
            such party; and

      d.    the performance of this Agreement by it will not require it to
            obtain the consent, waiver or approval of any person and will not
            violate, result in a breach of or constitute a default under any
            statute, regulation, agreement, judgment, consent, or decree by
            which it is bound.

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                                   II. Quorum

Each Affiliated Shareholder agrees that, at any time it owns any Cooper Bermuda
capital stock and such stock has rights to vote at any annual, special or other
general meeting of Cooper Bermuda shareholders, and at any adjournment or
adjournments thereof, it shall cause all such capital stock to be present in
person or by proxy at such meeting for purposes of determining whether a quorum
is present at any such meeting.

                                  III. Voting

Each Affiliated Shareholder agrees that, at any time it owns any Cooper Bermuda
capital stock and such stock has rights to vote at any annual, special or other
general meeting or pursuant to a written resolution of Cooper Bermuda
shareholders, it will vote such shares for and against and abstain from voting
with respect to any proposal in the same proportion that the holders of the
outstanding shares of Class A common stock held and voted by non-affiliates of
Cooper Bermuda have voted for and against and abstained from voting with respect
to such proposal. CBI hereby appoints Cooper Ohio as proxy, with full power of
substitution, to vote all shares of Cooper Bermuda capital stock owned by each
such company in the manner described in the preceding sentence.

                           IV. Transfer Restrictions

a.    Each Affiliated Shareholder hereby agrees that all transfers of Cooper
      Bermuda capital stock shall be made in accordance with the applicable
      rules of the New York Stock Exchange, or any other exchange on which the
      capital stock of Cooper Bermuda is listed.

b.    Each Affiliated Shareholder agrees that any transfer of Cooper Bermuda
      stock by it to an affiliate of Cooper Bermuda will be subject to this
      Agreement and such transferee will agree in writing to be bound by the
      terms and provisions of this Agreement.

                          V. Miscellaneous Provisions

a.    Binding Effect. This Agreement and all the provisions hereof shall be
      binding upon and inure to the benefit of the parties hereto and their
      respective successors and permitted assigns. Neither this Agreement nor
      any of the rights, interests or obligations hereunder shall be assigned by
      any of the parties hereto without the prior written consent of the other
      parties. The parties hereto agree to cause their subsidiaries to agree in
      writing to be bound by the terms of this Agreement prior to, or
      immediately upon, the acquisition of shares of Cooper Bermuda stock by
      such subsidiaries.

b.    Amendments. This Agreement may not be modified, amended, altered or
      supplemented except upon the execution and delivery of a written agreement
      executed by each of the parties hereto. However, any party may waive any
      condition to the obligations of any other party hereunder.

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c.    Notices. All notices, requests, demands and other communications required
      or permitted hereunder shall be in writing and shall be deemed to have
      been duly given if delivered by hand or mail, certified or registered mail
      (return receipt requested) with postage prepaid:

                  If to Cooper Bermuda, to:

                  Cooper Industries, Ltd.
                  600 Travis, Suite 5800
                  Houston, TX 77002
                  Attention: Office of the Corporate Secretary

                  If to Cooper Ohio, to:

                  Cooper Industries, Inc.
                  600 Travis, Suite 5800
                  Houston, TX 77002
                  Attention: General Counsel

                  If to CBI, to:

                  Cooper Bermuda Investments, Ltd.
                  600 Travis, Suite 5800
                  Houston, TX 77002
                  Attention:  Office of the Corporate Secretary

      or to such other address as any party may have furnished to the others in
      writing in accordance herewith.

d.    Applicable Law. This Agreement and the legal relations among the parties
      hereto arising from this Agreement shall be governed by and construed in
      accordance with the laws of Bermuda, without reference to or application
      of any conflicts of law principles.

e.    Counterparts. This Agreement may be executed simultaneously in two or more
      counterparts, each of which shall be deemed original but all of which
      shall constitute one and the same instrument.

f.    Entire Agreement. This Agreement constitutes the entire agreement and
      understanding of the parties hereto in respect of the subject matter
      contained herein. There are no restrictions, promises, warranties,
      covenants or undertakings, other than those expressly set forth or
      referred to herein. This Agreement supersedes all prior agreements and
      understandings among the parties with respect to such subject matter.

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IN WITNESS WHEREOF, the parties hereto have caused this Agreement to be duly
executed and made and entered into as of the date first set forth above.

                                      COOPER INDUSTRIES, LTD.

                                      By: /s/ Diane K. Schumacher
                                          -----------------------------
                                          Diane K. Schumacher
                                          Senior Vice President, General Counsel
                                          and Chief Compliance Officer

                                      COOPER INDUSTRIES, INC.

                                      By: /s/ Kirk S. Hachigian
                                          -----------------------------
                                          Kirk S. Hachigian
                                          President

                                      COOPER BERMUDA INVESTMENTS, LTD.

                                      By: /s/ E. Daniel Leightman
                                          -----------------------------
                                          E. Daniel Leightman
                                          President

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