Fulbright & Jaworski L.L.P. A Registered Limited Liability Partnership Fulbright Tower 1301 McKinney, Suite 5100 Houston, Texas 77010-3095 www.fulbright.com

Exhibit 5.1

Fulbright & Xxxxxxxx L.L.P.
A Registered Limited Liability Partnership
Fulbright Tower
0000 XxXxxxxx, Xxxxx 0000
Xxxxxxx, Xxxxx 00000-0000
xxx.xxxxxxxxx.xxx

Telephone: (000) 000-0000 Facsimile: (000) 000-0000

March 25, 2008

Xxxxxx Industries, Ltd.
Xxxxxx B-Line, Inc
Xxxxxx Bussmann, LLC
Xxxxxx Xxxxxx-Xxxxx, LLC
Xxxxxx Lighting, LLC
Xxxxxx Power Systems, LLC
Xxxxxx Wiring Devices, Inc.
Xxxxxx US, Inc.

c/o Cooper Industries, Ltd.
000 Xxxxxx
Xxxxxxx, Xxxxx 00000

Ladies and Gentlemen:

We have acted as special United States counsel to Xxxxxx Industries, Ltd., a Bermuda company (“Cooper Parent”) and Xxxxxx US, Inc., a Delaware corporation (“Xxxxxx US”), in connection with the proposed offering by Xxxxxx US of $300,000,000 aggregate principal amount of Xxxxxx US’s 5.45% Senior Notes due 2015 (the “Notes”) to be fully and unconditionally guaranteed by Cooper Parent, Xxxxxx B-Line, Inc., a Delaware corporation, Xxxxxx Bussmann, LLC, a Delaware limited liability company, Cooper Xxxxxx-Xxxxx, LLC, a Delaware limited liability company, Xxxxxx Lighting, LLC, a Delaware limited liability company, Xxxxxx Power Systems, LLC, a Delaware limited liability company, and Xxxxxx Wiring Devices, Inc., a New York corporation (collectively, the “Subsidiary Guarantors” and with Cooper Parent, the “Guarantors”) pursuant to guarantees (the “Guarantees”). The Notes are to be issued pursuant to an Indenture dated June 18, 2007, as amended by a Second Supplemental Indenture anticipated to be dated March 27, 2008 (as so amended and supplemented, the “Indenture”) among Cooper Parent, Xxxxxx US, the subsidiary guarantors named therein and Deutsche Bank Trust Company Americas, as trustee, which establishes the forms and terms of the Notes pursuant to the Indenture. We refer to the Registration Statement on Form S-3 (Registration No. 333-143688) (the “Registration Statement”), filed with the Securities and Exchange Commission (the “Commission”) by Xxxxxx US and the Guarantors on June 13, 2007, including the base prospectus contained therein, and the prospectus supplement (the “Prospectus Supplement”) filed with the Commission on March 25, 2008, relating to the offering of the Notes.

We have examined such corporate records, documents and questions of law as we have deemed necessary or appropriate for the purposes of this opinion. In such examinations, we have

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March 25, 2008
Page 2

assumed the genuineness of signatures and the conformity to the originals of the documents supplied to us as copies. As to various questions of fact material to this opinion, we have relied upon statements and certificates of officers and representatives. Without limiting the foregoing, we have examined the Underwriting Agreement, dated March 24, 2008, among Cooper Parent, Xxxxxx US, the subsidiary guarantors named therein, Deutsche Bank Securities Inc., X. X. Xxxxxx Securities Inc. and UBS Securities LLC and the other underwriters(the “Underwriters”) named therein (the “Underwriting Agreement”). In connection with rendering the opinions set forth below, we have assumed that any supplemental indenture relating to the Securities will be duly authorized, executed and delivered by the parties thereto and each person signing the Indenture will have the legal capacity and authority to do so.

Based upon the foregoing, and subject to the limitations, qualifications, assumptions and exceptions stated herein, we are of the opinion that:

(i) The Notes have been duly authorized and, when executed and authenticated in accordance with the provisions of the Indenture and delivered to and paid for by the Underwriters pursuant to the Underwriting Agreement, will, under the laws of the State of New York, constitute legal and binding obligations of Xxxxxx US; and

(ii) Assuming Xxxxxx US has the necessary corporate right, power and authority to execute and deliver, and perform its obligations under, the Indenture, the Guarantees will, under the laws of the State of New York, constitute legal and binding obligations of each of the Guarantors.

Each of the opinions above is subject to any applicable bankruptcy, insolvency (including, without limitation, all laws relating to fraudulent transfers), reorganization, moratorium and similar laws relating to or affecting creditors’ rights generally and to general equitable principles (regardless of whether enforcement is sought in a proceeding in equity or at law).

The foregoing opinions are limited to the laws of the State of New York, the General Corporation Law of the State of Delaware, the Delaware Limited Liability Company Act (including the applicable provisions of the Delaware Constitution and the reported judicial decisions interpreting these laws) and the federal laws of the United States of America.

We hereby consent to the references to this firm under the caption “Legal Matters” in the Prospectus Supplement and to the filing of this opinion as an exhibit to the Registration Statement. By giving such consent, we do not admit that we are within the category of persons whose consent is required under Section 7 of the Securities Act of 1933 or the rules and regulations thereunder.

Very truly yours,

/s/ FULBRIGHT & XXXXXXXX L.L.P.

Fulbright & Xxxxxxxx L.L.P.