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                                                                   Exhibit 3.5.1

                               ARTICLES OF MERGER

                                       OF

                           R. D. ARIZONA LADDER CORP.
                        (an Arizona business corporation)

                                       AND

                                   WERNER CO.
                          (a Pennsylvania corporation)


         Pursuant to the provisions of the Business Corporation Law of 1988 of
the Commonwealth of Pennsylvania, as amended, and the provisions of Chapters 1
through 17 of Title 10, of the Arizona Revised Statutes, governing the merger of
a wholly-owned subsidiary business corporation into its parent corporation, the
undersigned business corporations hereby submit the following Articles of
Merger.

         1.       The name of the subsidiary corporation, which is a business
                  corporation organized under the laws of the State of Arizona,
                  and which is subject to the provisions of Chapters 1 through
                  17 of Title 10, Arizona Revised Statutes, is R. D. ARIZONA
                  LADDER CORP.

         2.       The name of the parent corporation and the surviving
                  corporation following the merger, which is a business
                  corporation organized under the laws of the Commonwealth of
                  Pennsylvania, and which is subject to the provisions of the
                  Business Corporation Law of 1988 of the Commonwealth of
                  Pennsylvania, as amended, is WERNER CO. ("WERNER").

         3.       The number of outstanding shares of R. D. ARIZONA is One
                  Thousand (1,000), all of which are of one class, and all of
                  which are owned by WERNER.

         4.       The address of the known place of business in Arizona of
                  WERNER is 402 North 37th Drive, Suite 101, Phoenix, Arizona,
                  85009. The name and the address of the statutory agent of
                  WERNER in Arizona is Corporation Service Company, 3636 North
                  Central Avenue, Phoenix, Arizona, 85012.

         5.       Shareholder approval was not required.



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         6.       The Business Corporation Law of 1988 of the Commonwealth of
                  Pennsylvania, as amended, and Chapters 1 through 17 of Title
                  10, of the Arizona Revised Statutes permit a merger of a
                  wholly-owned subsidiary business corporation into a parent
                  business corporation of another jurisdiction and the merger of
                  R. D. ARIZONA into WERNER is in compliance with the laws of
                  the Commonwealth of Pennsylvania and the State of Arizona.

         7.       The registered address of the surviving corporation in the
                  Commonwealth of Pennsylvania and the address to which the
                  Arizona Corporation Commission may forward a copy of any
                  process served on it against the surviving corporation is:
                  Werner Co. 93 Werner Road, Greenville, Pennsylvania 16125.

         8.       The effective time and date of the merger herein provided for
                  shall be 12:01 a.m. on May 18, 1998.

         9.       The Plan of Merger is set forth in full in Exhibit A attached
                  hereto and made a part hereof.


Executed on May 12, 1998.

                                 R. D. ARIZONA LADDER CORP.


                                  /s/ Donald W. Resnick
                                 ------------------------------------------  

                                 By:  Donald W. Resnick
                                      Treasurer and Chief Financial Officer


                                 WERNER CO.


                                  /s/ Donald W. Resnick
                                 ------------------------------------------  

                                 By:  Donald W. Resnick
                                      Treasurer and Chief Financial Officer




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                                   EXHIBIT "A"

                                 PLAN OF MERGER



         The following is the Plan of Merger for merging R. D. ARIZONA LADDER
CORP., an Arizona business corporation ("R. D. ARIZONA") into WERNER CO., a
Pennsylvania business corporation ("WERNER") as approved on May 12, 1998 by
resolution of the Boards of Directors of R. D. ARIZONA and WERNER.



         10.      R. D. ARIZONA shall, pursuant to the provisions of the
                  Business Corporation Law of 1988 of the Commonwealth of
                  Pennsylvania, as amended, and pursuant to the provisions of
                  Chapters 1 through 17 of Title 10 of the Arizona Revised
                  Statutes, be merged into WERNER, which shall be the surviving
                  corporation upon the effective date of the merger in the
                  Commonwealth of Pennsylvania and which shall continue to exist
                  as said surviving corporation pursuant to the provisions of
                  the Business Corporation Law of 1988 of the Commonwealth of
                  Pennsylvania, as amended. The separate existence of R. D.
                  ARIZONA, which is a wholly-owned subsidiary of WERNER, shall
                  cease upon the effective date of the merger in accordance with
                  the provisions of Chapters 1 through 17 of Title 10 of the
                  Arizona Revised Statutes.

         11.      The Articles of Incorporation and Bylaws of Werner upon the
                  effective date of the merger in the Commonwealth of
                  Pennsylvania shall be the Articles of Incorporation and Bylaws
                  of the surviving corporation.

         12.      The issued shares of capital stock of R. D. ARIZONA shall not
                  be converted or exchanged in any manner, but each said share
                  which is issued as of the effective time and date of the
                  merger shall be cancelled and retired. The issued shares of
                  capital stock of WERNER shall not be changed as a result of
                  the merger.

         13.      The Boards of Directors and the proper officers of R. D.
                  ARIZONA and of WERNER are hereby authorized, empowered, and
                  directed to do any and all acts and things, and to make,
                  execute, deliver, file, and/or record any and all instruments,
                  papers, and documents which shall be or become necessary,
                  proper, or convenient to carry out or put into effect any of
                  the provisions of this Plan of Merger or of the merger herein
                  provided for.



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Executed on May 12, 1998

                                      R. D. ARIZONA LADDER CORP,
                                      d/b/a R. D. WERNER CO., INC. - ARIZONA


                                       /s/ Donald W. Resnick
                                      -----------------------------------------

                                      By:  Donald W. Resnick
                                           Treasurer and Chief Financial Officer

                                      WERNER CO.


                                       /s/ Donald W. Resnick
                                      -----------------------------------------

                                      By:  Donald W. Resnick
                                           Treasurer and Chief Financial Officer