Exhibit 10.21

PROMISSORY NOTE

|$196,311.00 |  | December 3, 2001
|----------- |  | ----------------

For
value received, Robert A. Shortt (the "Borrower"), promises to pay to the order of Water Pik Technologies, Inc., a Delaware corporation (the "Lender"), the principal sum of
One Hundred Ninety Six Thousand Three Hundred Eleven and 00/100 Dollars ($196,311.00), plus interest thereon at the semi-annual compounding rate of 4.99%, payable as set forth below.

This
Promissory Note (the "Note") evidences a loan from the Lender to the Borrower for the purpose of facilitating Borrower's satisfaction of a financial obligation to CSK Auto
Corporation ("CSK"), Borrower's former employer, incurred by Borrower pursuant to CSK's Senior Executive Stock Loan Plan. This Note is the result of a commitment made by the Lender in connection with
recruiting Borrower as an employee of Lender. This Note is secured by a pledge of shares of common stock of CSK (the "Pledged CSK Shares") and shares of common stock ("Common Stock") par value $0.01
per share of the Lender (the "Pledged PIK Shares") described inExhibit Ahereto.

Prior
to November 29, 2004, no portion of the principal amount hereof shall be due and payable except upon the occurrence of an Event of Default (as hereinafter defined), and
interest hereon shall be payable in arrears, in whole or in part, from cash dividends, if any, on the Pledged CSK Shares and the Pledged PIK Shares. On November 29, 2004, accrued but unpaid
interest shall be added to the then
outstanding principal amount hereof, and such revised principal amount plus interest thereon shall be paid by the Borrower to the Lender in substantially equal monthly payments, commencing on the
first day of the month immediately following November 29, 2004 and on the first day of each month thereafter, with all outstanding principal and interest to be paid no later than
November 29, 2009. For the convenience of the Borrower and not as a condition to the Borrower's obligations hereunder, as soon as practicable after November 29, 2004, the Lender shall
deliver to the Borrower an amortization schedule with respect to the loan evidenced hereby which schedule shall reflect the monthly payment schedule described above.

Payment
of principal and interest shall be made in lawful money of the United States of America or in shares of Common Stock held by Borrower, other than the Pledged CSK Shares or the
Pledged PIK Shares, shares of Common Stock designated as being subject to the Lender's Stock Acquisition and Retention Program ("SARP"), shares of Common Stock credited to Borrower's account pursuant
to the Lender's qualified defined contribution plan or shares of Common Stock subject to outstanding but unexercised stock options of the Borrower; provided, however that shares of Common Stock
purchased or designated under the SARP can be used to pay principal and/or interest if at the time of such payment, Borrower is an active employee of Water Pik Technologies, Inc. or a
subsidiary of Water Pik Technologies, Inc. or the Participant's employment is terminated due to death, disability, or retirement pursuant to the retirement policy of Water Pik
Technologies, Inc. Principal and interest shall be payable or deliverable to Lender at:



Any
shares of Common Stock delivered as payment hereunder shall be valued at their fair market value (as defined below), determined as of the business day preceding the date of delivery
to the Lender. For this purpose, "business day" means any day on which the New York Stock Exchange shall be open for trading. "Fair market value" means the average of the high and low trading prices
of the Common Stock as reported on the New York Stock Exchange or, if the Common Stock is not then traded on the New York Stock Exchange, on such other national securities exchange on which the Common
Stock is admitted to trade, or, if none, on the National Association of Securities Dealers Automated Quotation System if the Common Stock is admitted for quotation thereon: provided,

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however, if there were no sales reported as of a particular date, fair market value shall be computed as of the last date preceding such date on which a sale was reported; provided, further, that if
any such exchange or quotation system is closed on any day on which fair market value is to be determined, fair
market value shall be determined as of the first date immediately preceding such date on which such exchange or quotation system was open for trading.

The
Borrower shall pay a late charge at a rate of two percent (2%) per month on any amount of principal or interest that is not paid within ten (10) days of the due date of such
amount.

Each
of the following events shall constitute an "Event of Default" and all such events shall collectively be referred to as "Events of Default":



Upon
the occurrence of an Event of Default specified above, the outstanding Principal Amount hereof and accrued interest hereon may be declared to be and shall thereupon become
immediately due and payable: provided, however, that upon the occurrence of an Event of Default described in clause (b) or (c) above, the outstanding principal amount hereof and accrued
interest hereon shall automatically become immediately due and payable.

The
principal amount of this Promissory Note may be prepaid by the Borrower at any time, in whole or in part, without penalty.

Demand,
presentation, protest, notice of dishonor and notice of default are hereby waived. In any action on this Promissory Note, Lender or its assigns need not produce or file this
Promissory Note, but need only produce or file a photocopy of this Promissory Note certified by Lender or its assignees to be a true and correct copy of this Promissory Note.

Notwithstanding
anything herein to the contrary, if at any time the interest or other amount treated as interest under applicable law ("Interest") hereunder exceeds the maximum lawful
rate (the "Maximum Rate") which may be charged in accordance with applicable laws, the rate of Interest hereunder shall be limited to the Maximum Rate.

All
notices or communications to the Borrower hereunder shall be in writing, addressed as follows:



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Any
such notice or communication shall be sent certified or registered mail, return receipt requested, postage prepaid, addressed as above (or to such other address as the Borrower may
designate in writing from time or time), and the actual date of receipt, as shown by the receipt therefor, shall determine the time at which notice was given.

This
Promissory Note shall be governed by and construed in accordance with the laws of the State of Delaware other than the conflict of laws provisions thereof.

WITNESS
the due execution hereof with intent to be legally bound.

|Witness: |  | BORROWER                           
|-------- |  | -----------------------------------
|         |  | /s/ROBERT A. SHORTTRobert A. Shortt

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EXHIBIT A
PLEDGED SECURITIES

|Stock                                                               |  | Certificate No. |  | No. of Shares
|------------------------------------------------------------------- |  | --------------- |  | -------------
|CSK Auto Corporation. (NYSE: CAO)
(the "Pledged CSK Shares")        |  |                 |  | 1,000        
|                                                                    |  |                 |  |              
|Water Pik Technologies, Inc. (NYSE: PIK)
(the "Pledged PIK Shares") |  | 8576            |  | 33,108       

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