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                                                                     EXHIBIT 4.2

                       AMENDMENT NO. 1 TO RIGHTS AGREEMENT

        This Amendment No. 1 to Rights Agreement (this "Amendment") is entered
into as of December 28, 2000, by and between WATER PIK TECHNOLOGIES, INC., a
Delaware corporation (the "Company"), and MELLON INVESTOR SERVICES LLC, a New
Jersey limited liability company, formerly known as CHASEMELLON SHAREHOLDER
SERVICES, L.L.C. (the "Rights Agent"), and amends the Rights Agreement dated as
of November 12, 1999, between the Company and the Rights Agent (the "Rights
Agreement").

        WHEREAS, this Amendment is entered into pursuant to Section 27 of the
Rights Agreement prior to the time that any Person, to the knowledge of the
Company, has become an Acquiring Person.

        NOW, THEREFORE, in consideration of the premises and the mutual
agreements herein set forth, the parties hereby agree as follows:

        1. Defined Terms. Terms defined in the Rights Agreement and used and not
otherwise defined herein shall have the meanings given to them in the Rights
Agreement.

        2. Amendment of Section 1.

            (a) Section 1(a) of the Rights Agreement is amended to add the
following sentence at the end thereof:

        Notwithstanding the foregoing provisions of this Section 1(a), the
        acquisition by the Purchasers collectively of an aggregate of 1,973,685
        Common Shares of the Company under the Purchase Agreement (the "New
        Securities"), in addition to the 386,800 Common Shares of the Company
        previously acquired by the Purchasers or their Affiliates or Associates
        (the "Old Securities," and collectively, with the New Securities, the
        "Purchaser Securities") shall not result in the Purchasers, or any of
        their Affiliates or Associates (as long as their Affiliates and
        Associates are not the Beneficial Owner of any Common Shares of the
        Company other than the Purchaser Securities), being deemed for purposes
        of the Rights Agreement, an "Acquiring Person" as defined in Section
        1(a) of the Rights Agreement; provided, however, that if either or both
        Purchasers, together with all Affiliates and Associates of such
        Purchasers, or any of their Affiliates or Associates become the
        Beneficial Owner of any additional Common Shares of the Company (other
        than the Purchaser Securities) so that any of them would, at any time
        after the effective date of this Amendment, be deemed to have Beneficial
        Ownership of 15% or more of the Common Shares of the Company then
        outstanding in accordance with Section 1(a) of the Rights Agreement,
        then such Purchaser or Purchasers and/or their Affiliate or Associate
        shall be deemed to be an "Acquiring Person" for all purposes of the
        Rights Agreement. Nothing contained in this Amendment shall exempt the
        application of the Rights Agreement to any Person or to any acquisition
        or Beneficial Ownership of Common Shares of the Company, other than the
        acquisition of the New Securities under the Purchase Agreement by the
        Purchasers at a time when the Purchasers and/or their Affiliates and
        Associates are the Beneficial Owners of the Old Securities.


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            (b) Section 1 of the Rights Agreement is further amended to add the
following definitions, which shall be inserted into Section 1 in alphabetical
order:

        "Purchase Agreement" shall mean the Stock Purchase Agreement to be
        entered into by and among the Purchasers and the Company under which the
        Purchasers will purchase the New Securities.

        "Purchasers" shall mean Special Value Bond Fund, LLC, a Delaware limited
        liability company, and Special Value Bond Fund II, LLC, a Delaware
        limited liability company.

        3. Effectiveness. This Amendment shall be deemed effective as of the
time immediately prior to the signing of the Purchase Agreement. Except as
amended hereby, the Rights Agreement shall remain in full force and effect and
shall be otherwise unaffected hereby.

        4. Miscellaneous. This Amendment shall be deemed to be a contract made
under the laws of the State of Delaware and for all purposes shall be governed
by and construed in accordance with the laws of such state. This Amendment may
be executed in any number of counterparts, each of such counterparts shall for
all purposes be deemed an original and all such counterparts shall together
constitute but one and the same instrument.

        IN WITNESS WHEREOF, the parties hereto have caused this Amendment to be
duly executed and attested, all as of the day and year first above written.


Attest:                                      WATER PIK TECHNOLOGIES, INC.


                                             By:
---------------------------------                -------------------------------
Name: Richard D. Tipton                          Name: Michael P. Hoopis
Title: VP & General Counsel                      Title: President and CEO


Attest:                                      MELLON INVESTOR SERVICES LLC


                                             By:
---------------------------------                -------------------------------
Name: Ronald Lug                                 Name: Joseph Cannata
Title: Vice President                            Title: Assistant Vice President


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