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                                                                     EXHIBIT 4.3

                                                                  EXECUTION COPY
                                                                  --------------

                             JOINDER TO AMENDED AND
                     RESTATED REGISTRATION RIGHTS AGREEMENT

          THIS JOINDER to the Amended and Restated Registration Rights
Agreement, dated as of March 3, 1998 by and among Sleepmaster Holdings L.L.C., a
New Jersey limited liability company (the "Company"), and certain
securityholders of the Company (the "Agreement"), is made and entered into as of
April 28, 2000 by and between the Company and Donald S. Simon, Jr. ("Holder").
Capitalized terms used herein but not otherwise defined shall have the meanings
set forth in the Agreement.

                  WHEREAS, Holder has acquired certain units of Common Interests
and the Agreement and the Company contemplates that Holder, as a holder of
Common Interests, may be entitled to become a party to the Agreement, and Holder
agrees to do so in accordance with the terms hereof.

                  NOW, THEREFORE, in consideration of the mutual covenants
contained herein and other good and valuable consideration, the receipt and
sufficiency of which are hereby acknowledged, the parties to this Joinder hereby
agree as follows:

                  1. Agreement to be Bound. Holder hereby agrees that upon
execution of this Joinder, it shall become a party to the Agreement and shall be
fully bound by, and subject to and entitled to the benefits of, all of the
covenants, terms and conditions of the Agreement as though an original party
thereto and shall be deemed a holder of Executive Registrable Securities for all
purposes thereof. In addition, Holder hereby agrees that all Common Interests
held by Holder shall be deemed Executive Registrable Securities for all purposes
of the Agreement.

                  2. Successors and Assigns. Except as otherwise provided
herein, this Joinder shall bind and inure to the benefit of and be enforceable
by the Company and its successors and assigns and Holder and any subsequent
holders of Common Interests and the respective successors and assigns of each of
them, so long as they hold any shares of Common Interests.

                  3. Counterparts. This Joinder may be executed in separate
counterparts each of which shall be an original and all of which taken together
shall constitute one and the same agreement.

                  4. Notices. For purposes of Section 12 of the Agreement, all
notices, demands or other communications to the Holder shall be directed to:

                            Mr. Donald S. Simon, Jr.
                      c/o Simon Mattress Manufacturing Co.
                            3777 Vaca Valley Parkway
                            Vacaville, CA 95688-9430
                          Telephone No.: (707) 446-7999
                          Telecopy No.: (707) 446-6057

                  5. GOVERNING LAW. THE LIMITED LIABILITY COMPANY LAWS OF THE
STATE OF NEW JERSEY WILL GOVERN ALL QUESTIONS CONCERNING THE RELATIVE RIGHTS OF
THE COMPANY AND ITS MEMBERS.
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ALL OTHER QUESTIONS CONCERNING THE CONSTRUCTION, VALIDITY AND INTERPRETATION OF
THIS JOINDER SHALL BE GOVERNED BY AND CONSTRUED IN ACCORDANCE WITH THE DOMESTIC
LAWS OF THE STATE OF NEW YORK, WITHOUT GIVING EFFECT TO ANY CHOICE OF LAW OR
CONFLICT OF LAW PROVISION OR RULE (WHETHER OF THE STATE OF NEW YORK OR ANY OTHER
JURISDICTION) THAT WOULD CAUSE THE APPLICATION OF THE LAWS OF ANY JURISDICTION
OTHER THAN THE STATE OF NEW YORK.

                  6. DESCRIPTIVE HEADINGS. The descriptive headings of this
Joinder are inserted for convenience only and do not constitute a part of this
Joinder.

                                    * * * * *

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                  IN WITNESS WHEREOF, the parties hereto have executed this
Joinder as of the date first above written.

                            SLEEPMASTER HOLDINGS L.L.C.


                            By: /s/ Charles Schweitzer
                               --------------------------------
                            Name: Charles Schweitzer
                            Title:   President & CEO


                            /s/ Donald S. Simon, Jr.
                            -----------------------------------
                            DONALD S. SIMON, JR.