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                                                                    Exhibit 4.04


                  STOCK OPTION AGREEMENT made as of the 31st day of October
2001, by and between CANTEL MEDICAL CORP., a Delaware corporation with principal
offices located at 150 Clove Road, Little Falls, New Jersey, 07424 (the
"Company"), and JOSEPH L. HARRIS, 209 Edenton Place, Villanova, Pennsylvania
19085 (the "Optionee").

                   ------------------------------------------

                  The Optionee is presently an employee of the Company and is
hereby granted an option to purchase shares of the Company's Common Stock, par
value $.10 per share ("Common Stock"), on the terms and conditions set forth
below.

                    NOW, THEREFORE, in consideration of the premises and for
other good and valuable consideration, receipt of which is hereby acknowledged,
the Company hereby grants the Optionee the option to acquire shares of the
Common Stock of the Company upon the following terms and conditions:

                  1.  GRANT OF OPTION.

                      (a) The Company hereby grants to the Optionee the right
and option (the "Option") to purchase up to 50,000 shares of Common Stock (the
"Shares"), to be issued upon the exercise hereof, fully paid and non-assessable,
during the following periods: (i) 16,667 Shares may be purchased commencing
October 31, 2001; (ii)an additional 16,667 Shares may be purchased commencing
October 31,


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2002; and (iii) an additional 16,666 Shares may be purchased commencing October
31, 2003.

                      (b)  The Option granted hereby shall expire and
terminate at 5:00 p.m. local time in New York, New York on October 30, 2011 (the
"Expiration Date") at which time the Optionee shall have no further right to
purchase any Shares not then purchased.

                  2.  EXERCISE PRICE. The exercise price of the Option shall be
$22.45 per Share, and shall be payable in cash or by certified check; provided,
however, that in lieu of payment in full in cash or by such check, the exercise
price (or balance thereof) may be paid in full or in part by the delivery and
transfer to the Company of Common Stock already owned by the Optionee and having
a fair market value (as determined by the Board of Directors in its absolute
discretion) equal to the cash exercise price (or balance thereof) for the number
of Shares as to which the Option is being exercised. The Company shall pay all
original issue or transfer taxes on the exercise of the Option.

                  3.  EXERCISE OF OPTION. The Optionee shall notify the Company
by registered or certified mail, return receipt requested, addressed to its
principal office, as to the number of Shares which he desires to purchase under
the Option, which notice shall be accompanied by payment of the Option exercise
price therefor as specified in Paragraph 2 above. As soon as practicable after
the


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receipt of such notice, the Company shall, at its principal office or another
mutually convenient location, tender to the Optionee certificates issued in the
Optionee's name evidencing the Shares purchased by the optionee hereunder.

                  4.  CONDITIONS OF EXERCISE. The Optionee (or his legal
representative following the death of the Optionee) shall have the right to
exercise the Option only while the Optionee is an employee of the Company;
provided, however, the Option may be exercised at any time within twenty four
(24) months after the date the Optionee ceases to be an employee, but only to
the extent that it was exercisable upon such date of termination and in no event
after the Expiration Date.

                  5.  NON-ASSIGNABILITY OF OPTION. The Optionee may not give,
grant, sell, exchange, transfer legal title, pledge, assign or otherwise
encumber or dispose of the Option herein granted or any interest therein,
otherwise than by will or the laws of descent and distribution and, except as
provided in Paragraph 4 hereof, the Option shall be exercisable only by the
Optionee.

                  6.  THE SHARES AS INVESTMENT. By accepting the Option, the
Optionee agrees for himself, his heirs and legatees that any and all Shares
purchased upon the exercise thereof shall be acquired for investment and not for
distribution, and upon the issuance of any or all of the Shares subject to the
Option, the Optionee, or his heirs or legatees receiving such Shares, shall


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deliver to the Company a representation in writing that such Shares are being
acquired in good faith for investment and not for distribution. The Company may
place a "stop transfer" order with respect to such Shares with its transfer
agent and may place an appropriate restrictive legend on the certificate(s)
evidencing such Shares.

                  7.  RESTRICTION OF ISSUANCE OF SHARES. The Optionee shall, if
so requested by the Company, represent and agree, in writing and in such form as
the Company shall determine, that any securities purchased by the Optionee upon
the exercise of this Option are being purchased for investment and not with a
view to the distribution thereof, and shall make such other or additional
representations and agreements and furnish such information as the Company may
in its reasonable discretion deem necessary or desirable to assure compliance by
the Company, on terms acceptable to the Company, with provisions of the
Securities Act of 1933 and any other applicable legal requirements. If at any
time the Company shall reasonably determine that the listing, registration or
qualification of the Shares subject to this Option upon any securities exchange
or under any state or federal law, or the consent or approval of any
governmental regulatory body, are necessary or desirable in connection with the
issuance or purchase of the Shares subject thereto, this Option may not be
exercised in whole or in part unless such listing, registration, qualification,

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consent or approval shall have been effected or obtained free of any conditions
not acceptable to the Company. The Optionee shall have no rights against the
Company if this Option is not exercisable by virtue of the foregoing provision.
The certificate representing any securities issued pursuant to the exercise of
this Option may, at the discretion of the Company, bear a legend in
substantially the following form:

                               "The securities represented by this
                      certificate have not been registered under the
                      Securities Act of 1933. The securities have been
                      acquired for investment and may not be pledged or
                      hypothecated and may not be sold or transferred in
                      the absence of an effective Registration Statement
                      for the securities under the Securities Act of 1933
                      or an opinion of counsel to the Company that
                      registration is not required under said Act. In the
                      event that a Registration Statement becomes effective
                      covering the securities or counsel to the Company
                      delivers a written opinion that registration is not
                      required under said Act, this certificate may be
                      exchanged for a certificate free from this legend."

                  8.  ADJUSTMENTS UPON CHANGES IN CAPITALIZATION.

                      (a)  In the event of changes in the outstanding
Shares by reason of stock dividends, split-ups, recapitalizations, mergers,
consolidations, combination, exchanges of shares, separations, reorganizations,
liquidations and the like, the number and class of Shares or the amount of cash
or other assets or securities available upon the exercise of the Option and the
exercise price thereof shall be correspondingly adjusted by the Company, to the
end that the Optionee's proportionate interest in the Company, any successor
thereto or in the cash, assets or other

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securities into which shares are converted or exchanged shall be maintained to
the same extent, as near as may be practicable, as immediately before the
occurrence of any such event.

                      (b) Any adjustment in the number of Shares shall apply
proportionately to only the then unexercised portion of the Option. If
fractional Shares would result from any such adjustment, the adjustment shall be
revised to the next higher whole number.

                      (c) In case the Company is merged or consolidated with
another corporation, or the property or shares of the Company are acquired by
another corporation, or the Optionee is discharged other than for cause, the
exercise schedule set forth in paragraph 1 above shall be waived and all options
for the entire 50,000 shares of the Company's Common Stock shall be immediately
exercisable by the Optionee pursuant to paragraph 3 above.

                      For purposes of this paragraph (c), merger or
consolidation with another corporation or acquisition by another corporation
shall be defined as the acquisition by another corporation of more than forty
percent (40%) of any of the then outstanding stock, voting power, or assets of
the Company.

                  9.  NO RIGHTS AS SHAREHOLDERS. The Optionee shall have no
rights as a shareholder in respect of the Shares as to which the Option shall
not have been exercised and payment made as herein provided.

                  10. BINDING EFFECT. Except as herein otherwise expressly
provided, this Agreement shall be binding upon and shall inure to

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the benefit of the parties hereto, their legal representatives and assigns.

                  11. GOVERNING LAW. This Agreement shall be governed by and
construed in accordance with the laws of the State of New Jersey applicable to
agreements made and to be performed wholly within the State of New Jersey.

                  IN WITNESS WHEREOF, the parties have executed this Agreement
as of the date and year first above written.



                                      CANTEL MEDICAL CORP.

                                      By: /s/ James P. Reilly
                                         ---------------------------------------
                                         James P. Reilly, President


                                      /s/ Joseph L. Harris
                                      ------------------------------------------
                                      Joseph L. Harris





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