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                                                                     Exhibit 4.4


                               SLEEPMASTER L.L.C.
                                       and
                         SLEEPMASTER FINANCE CORPORATION

                                   as Issuer,

                 11% SERIES B SENIOR SUBORDINATED NOTES DUE 2009


                             SUPPLEMENTAL INDENTURE

                          Dated as of February 8, 2000


                     UNITED STATES TRUST COMPANY OF NEW YORK


                                     Trustee

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                                    SUPPLEMENTAL INDENTURE (this "Supplemental
                           Indenture"), dated as of February 8, 2000, among ADAM
                           WUEST CORPORATION, a Delaware corporation (the "New
                           Guarantor Subsidiary"), a subsidiary of SLEEPMASTER
                           L.L.C., a New Jersey limited liability company (the
                           "Company"); THE COMPANY and SLEEPMASTER FINANCE
                           CORPORATION, a Delaware corporation ("Finance Corp."
                           and, together with the Company, the "Issuers"); PALM
                           BEACH BEDDING COMPANY, a Florida corporation, HERR
                           MANUFACTURING COMPANY, a Pennsylvania corporation,
                           and LOWER ROAD ASSOCIATES, LLC, a New Jersey limited
                           liability company (the three preceding entities
                           together, the "Existing Guarantor Subsidiaries"); and
                           UNITED STATES TRUST COMPANY OF NEW YORK, a New York
                           banking association, as trustee under the Indenture
                           referred to below (the "Trustee").


                              W I T N E S S E T H :

                  WHEREAS, the Issuers have heretofore executed and delivered to
the Trustee an Indenture (the "Indenture"), dated as of May 18, 1999, providing
for the issuance of an aggregate principal amount of $115,000,000 of 11% Series
B Senior Subordinated Notes due 2009 (the "Securities");

                  WHEREAS, Section 1013 of the Indenture provides that under
certain circumstances the Company is required to cause the New Guarantor
Subsidiary to execute and deliver to the Trustee a supplemental indenture
pursuant to which the New Guarantor Subsidiary shall unconditionally guarantee
all of the Company's obligations under the Securities pursuant to a Subsidiary
Guaranty on the terms and conditions set forth herein; and

                  WHEREAS, pursuant to Section 901 of the Indenture, the
Trustee, the Company and Existing Guarantor Subsidiaries are authorized to
execute and deliver this Supplemental Indenture;

                  NOW THEREFORE, in consideration of the foregoing and for other
good and valuable consideration, the receipt of which is hereby acknowledged,
the New Guarantor Subsidiary, the Company, the Existing Guarantor Subsidiaries
and the Trustee mutually covenant and agree for the equal and ratable benefit of
the Holders of the Securities as follows:

                  1. Definitions. (a) Capitalized terms used herein without
definition shall have the meanings assigned to them in the Indenture.

                           (b) For all purposes of this Supplemental Indenture,
except as otherwise herein expressly provided or unless the context otherwise
requires: (i) the terms and expressions used herein shall have the same meanings
as corresponding terms and expressions used in the


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Indenture; and (ii) the words "herein," "hereof" and "hereby" and other words of
similar import used in this Supplement refer to this Supplement as a whole and
not to any particular section hereof.

                  2. Agreement to Guarantee. The New Guarantor Subsidiary hereby
agrees, jointly and severally with all other Guarantor Subsidiaries, to
Guarantee the Company's obligations under the Securities on the terms and
subject to the conditions set forth in Article XIV of the Indenture and to be
bound by all other applicable provisions of the Indenture.

                  3. Ratification of Indenture; Supplemental Indentures Part of
Indenture. Except as expressly amended hereby, the Indenture is in all respects
ratified and confirmed by the parties hereto and all the terms, conditions and
provisions thereof shall remain in full force and effect. This Supplemental
Indenture shall form a part of the Indenture for all purposes, and every holder
of Securities heretofore or hereafter authenticated and delivered shall be bound
hereby.

                  4. Governing Law. THIS SUPPLEMENTAL INDENTURE SHALL BE
GOVERNED BY, AND CONSTRUED IN ACCORDANCE WITH, THE LAWS OF THE STATE OF NEW YORK
BUT WITHOUT GIVING EFFECT TO APPLICABLE PRINCIPLES OF CONFLICTS OF LAW TO THE
EXTENT THAT THE APPLICATION OF THE LAWS OF ANOTHER JURISDICTION WOULD BE
REQUIRED THEREBY.

                  5. Trustee Makes No Representation. The Trustee makes no
representation as to the validity or sufficiency of this Supplemental Indenture.

                  6. Counterparts. The parties may sign any number of copies of
this Supplemental Indenture. Each signed copy shall be an original, but all of
them together represent the same agreement.

                  7. Effect of Headings. The Section headings herein are for
convenience only and shall not effect the construction thereof.

                                    * * * * *


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                  IN WITNESS WHEREOF, the parties hereto have caused this
Supplemental Indenture to be duly executed as of the date first above written.

                                       ADAM WUEST CORPORATION

                                       by
                                              /s/ James P. Koscica
                                       ------------------------------------
                                       Name:    James P. Koscica
                                       Title:   Executive Vice President and
                                                Chief Financial Officer


                                       SLEEPMASTER L.L.C.

                                       by
                                              /s/ James P. Koscica
                                       ------------------------------------
                                       Name:    James P. Koscica
                                       Title:   Executive Vice President and
                                                Chief Financial Officer


                                       SLEEPMASTER FINANCE CORPORATION

                                       by
                                              /s/ James P. Koscica
                                       ------------------------------------
                                       Name:    James P. Koscica
                                       Title:   Executive Vice President and
                                                Chief Financial Officer


                                       PALM BEACH BEDDING COMPANY

                                       by
                                              /s/ James P. Koscica
                                       ------------------------------------
                                       Name:    James P. Koscica
                                       Title:   Executive Vice President and
                                                Chief Financial Officer


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                                       HERR MANUFACTURING COMPANY

                                       by
                                              /s/ James P. Koscica
                                       ------------------------------------
                                       Name:    James P. Koscica
                                       Title:   Executive Vice President and
                                                Chief Financial Officer


                                       LOWER ROAD ASSOCIATES, LLC

                                       by
                                              /s/ James P. Koscica
                                       ------------------------------------
                                       Name:    James P. Koscica
                                       Title:   Executive Vice President and
                                                Chief Financial Officer


                                       UNITED STATES TRUST COMPANY
                                       OF NEW YORK as Trustee

                                       by
                                             /s/ Margaret M. Ciesmelewski
                                       ------------------------------------
                                       Name:    Margaret M. Ciesmelewski
                                       Title:   Assistant Vice President


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