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                             PROMISSORY NOTE                      EXHIBIT 10.168

$825,000.00                                                   September 15, 2004

      FOR VALUE RECEIVED, on or before September 15, 2009 ("Maturity Date"), the
undersigned and if more than one, each of them, jointly and severally
(hereinafter referred to as "Borrower"), promises to pay to the order of BANK
ONE, NA, with its main office in Chicago, Illinois ("Bank") at its offices in
Tarrant County, Texas at 1301 S. Bowen Road, Suite 150, Arlington, Texas 76013,
the principal amount of EIGHT HUNDRED TWENTY-FIVE THOUSAND AND NO/100 DOLLARS
($825,000.00) ("Total Principal Amount"), or such amount less than the Total
Principal Amount which has been advanced to Borrower if the total amount
advanced under this Promissory Note ("Note") is less than the Total Principal
Amount, together with interest on such portion of the Total Principal Amount
which has been advanced to Borrower from the date advanced until paid at a
fluctuating rate per annum which shall from day to day be equal to the lesser of
(a) the Maximum Rate (as hereinafter defined), or (b) a rate ("Contract Rate"),
calculated on the basis of the actual days elapsed but computed as if each year
consisted of 360 days, equal to the sum of (i) the Prime Rate (as hereinafter
defined), plus (ii) one-fourth percent (.25%); provided, however, that if at any
time the Contract Rate shall exceed the Maximum Rate, thereby causing the
interest on this Note to be limited to the Maximum Rate, then any subsequent
reduction in the Prime Rate shall not reduce the rate of interest on this Note
below the Maximum Rate until the total amount of interest accrued on this Note
equals the amount of interest which would have accrued on this Note if the
Contract Rate had at all times been in effect.

      The term "Maximum Rate," as used herein, shall mean at the particular time
in question the maximum rate of interest which, under applicable law, may then
be charged on this Note. If such maximum rate of interest changes after the date
hereof and this Note provides for a fluctuating rate of interest, the Maximum
Rate shall be automatically increased or decreased, as the case may be, without
notice to Borrower from time to time as of the effective date of each change in
such Maximum Rate. If applicable law ceases to provide for such a maximum rate
of interest, the Maximum Rate shall be equal to eighteen percent (18%) per
annum.

      The term Prime Rate, as used herein, shall mean a rate per annum equal to
the prime rate of interest announced from time to time by Bank One, NA or its
parent (which is not necessarily the lowest rate charged to any customer),
changing when and as said prime rate changes, each change in the rate to be
charged on this Note to become effective without notice to Borrower on the
effective date of each change in the Maximum Rate or the Prime Rate, as the case
may be.

      Interest on this Note is computed by applying the ratio of the annual
interest rate over a year of 360 days, multiplied by the outstanding principal
balance, multiplied by the actual number of days the principal balance is
outstanding.

      The principal of and all accrued but unpaid interest on this Note shall be
due and payable without offset or reduction as follows:

      (a)   Principal and interest shall be amortized on the basis of a fifteen
            (15) year term payable in monthly installments of principal and
            interest in the amount of Six Thousand, Four Hundred Seventeen and
            11/100 Dollars ($6,417.11) commencing on October 15, 2004, and
            continuing on the 15th day of each month thereafter through
            September 15, 2005. Interest shall be adjusted with each change in
            the Prime Rate. Each such payment shall be applied first to accrued
            but unpaid interest and then to principal. Commencing on October
            15th of each year beginning in 2005, the monthly principal and
            interest installments thereafter due and payable shall be adjusted
            annually based on the remaining portion of the fifteen (15) year
            amortization period and the Prime Rate in effect on the 15th day of
            the preceding September, plus one-fourth percent (.25%). In the
            event the Prime Rate shall increase to a rate such that the monthly
            payment of principal and interest then payable shall not be
            sufficient to equal the total unpaid interest accrued to such
            payment date, then Borrower shall pay monthly an amount equal to the
            interest due on such payment date.

      (b)   The outstanding principal balance of this Note, together with all
            accrued but unpaid interest, shall be due and payable on the
            Maturity Date.

      If a payment is ten (10) or more days late, Borrower will pay a
delinquency charge in an amount equal to the greater of (i) $25.00, or (ii) 5.0%
of the amount of the delinquent payment up to the maximum amount of $1,500.00
per late charge. Upon default, including failure to pay upon final maturity,
Bank, at its option, may also, if permitted under applicable law, do one or both
of the following: (a) increase the applicable interest rate on this Note three
(3.00) percentage points, and (b) add any unpaid accrued interest to principal
and such sum will bear interest therefrom until paid at the rate provided in
this Note (including any increased rate). The interest rate will not exceed the
maximum rate permitted by applicable law.

      Borrower may from time to time prepay all or any portion of the principal
of this Note without premium or penalty. Unless otherwise agreed to in writing,
or otherwise required by applicable law, payments will be applied first to
unpaid accrued interest, then to principal, and any remaining amount to any
unpaid collection costs, late charges and other charges; provided, however, upon
delinquency or other default, Bank reserves the right to apply payments among
principal, interest, late charges, collection costs and other charges, at its
discretion. All prepayments shall be applied to the indebtedness owing hereunder
in such order and manner as Bank may from time to time determine in its sole
discretion. All payments and prepayments of principal of or interest on this
Note shall be made in lawful money of the United States of America in
immediately available funds, at the address of Bank indicated above, or such
other place as the holder of this Note shall designate in writing to Borrower.
If any payment of principal of or interest on this Note shall become due on a
day which is not a Business Day (as hereinafter defined), such payment shall be
made on the next succeeding Business Day and any such extension of time shall be
included in computing interest in connection with such payment. As used herein,
the term "Business Day" shall mean any day other than a Saturday, Sunday or any
other day on which national banking associations are authorized to be closed.
The books and records of Bank shall be prima facie evidence of all outstanding
principal of and accrued and unpaid interest on this Note.

      This Note has been executed and delivered pursuant to that certain Loan
Agreement dated December 31, 2003 by and between Borrower and Bank ("Loan
Agreement"), and is secured by, inter alia,a Deed of Trust, Security Agreement
and Assignment of Rents and Leases of even date herewith from Borrower in favor
of Douglass J. Kroiss, Trustee for the benefit of the Bank, covering certain
real property situated in Dallas County, Texas, as more particularly described
therein.

      This Note, the Loan Agreement and all other documents evidencing,
securing, governing, guaranteeing and/or pertaining to this Note, including but
not limited to those documents described above, are hereinafter collectively
referred to as the "Loan Documents." The holder of this Note is entitled to the
benefits and security provided in the Loan Documents.

PROMISSORY NOTE

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      Borrower agrees that no advances under this Note shall be used for
personal, family or household purposes, and that all advances hereunder shall be
used solely for business, commercial, investment, or other similar purposes.

      Borrower agrees that upon the occurrence of any one or more of the
following events of default ("Event of Default"):

      (a)   failure of Borrower to pay any installment of principal of or
            interest on this Note or on any other indebtedness of Borrower to
            Bank when due; or

      (b)   the occurrence of any event of default specified in any of the other
            Loan Documents; or

      (c)   the bankruptcy or insolvency of, the assignment for the benefit of
            creditors by, or the appointment of a receiver for any of the
            property of, or the liquidation, termination, dissolution or death
            or legal incapacity of, any party liable for the payment of this
            Note, whether as maker, endorser, guarantor, surety or otherwise;

the holder of this Note may, at its option, without further notice or demand,
(i) declare the outstanding principal balance of and accrued but unpaid interest
on this Note at once due and payable, (ii) refuse to advance any additional
amounts under this Note, (iii) foreclose all liens securing payment hereof, (iv)
pursue any and all other rights, remedies and recourses available to the holder
hereof, including but not limited to any such rights, remedies or recourses
under the Loan Documents, at law or in equity, or (v) pursue any combination of
the foregoing.

      The failure to exercise the option to accelerate the maturity of this Note
or any other right, remedy or recourse available to the holder hereof upon the
occurrence of an Event of Default hereunder shall not constitute a waiver of the
right of the holder of this Note to exercise the same at that time or at any
subsequent time with respect to such Event of Default or any other Event of
Default. The rights, remedies and recourses of the holder hereof, as provided in
this Note and in any of the other Loan Documents, shall be cumulative and
concurrent and may be pursued separately, successively or together as often as
occasion therefore shall arise, at the sole discretion of the holder hereof. The
acceptance by the holder hereof of any payment under this Note which is less
than the payment in full of all amounts due and payable at the time of such
payment shall not (i) constitute a waiver of or impair, reduce, release or
extinguish any right, remedy or recourse of the holder hereof, or nullify any
prior exercise of any such right, remedy or recourse, or (ii) impair, reduce,
release or extinguish the obligations of any party liable under any of the Loan
Documents as originally provided herein or therein.

      This Note and all of the other Loan Documents are intended to be performed
in accordance with, and only to the extent permitted by, all applicable usury
laws. If any provision hereof or of any of the other Loan Documents or the
application thereof to any person or circumstance shall, for any reason and to
any extent, be invalid or unenforceable, neither the application of such
provision to any other person or circumstance nor the remainder of the
instrument in which such provision is contained shall be affected thereby and
shall be enforced to the greatest extent permitted by law. It is expressly
stipulated and agreed to be the intent of the holder hereof to at all times
comply with the usury and other applicable laws now or hereafter governing the
interest payable on the indebtedness evidenced by this Note. If the applicable
law is ever revised, repealed or judicially interpreted so as to render usurious
any amount called for under this Note or under any of the other Loan Documents,
or contracted for, charged, taken, reserved or received with respect to the
indebtedness evidenced by this Note, or if Bank's exercise of the option to
accelerate the maturity of this Note, or if any prepayment by Borrower results
in Borrower having paid any interest in excess of that permitted by law, then it
is the express intent of Borrower and Bank that all excess amounts theretofore
collected by Bank be credited on the principal balance of this Note (or, if this
Note and all other indebtedness arising under or pursuant to the other Loan
Documents have been paid in full, refunded to Borrower), and the provisions of
this Note and the other Loan Documents immediately be deemed reformed and the
amounts thereafter collectable hereunder and thereunder reduced, without the
necessity of the execution of any new document, so as to comply with the then
applicable law, but so as to permit the recovery of the fullest amount otherwise
called for hereunder or thereunder. All sums paid, or agreed to be paid, by
Borrower for the use, forbearance, detention, taking, charging, receiving or
reserving of the indebtedness of Borrower to Bank under this Note or arising
under or pursuant to the other Loan Documents shall, to the maximum extent
permitted by applicable law, be amortized, prorated, allocated and spread
throughout the full term of such indebtedness until payment in full so that the
rate or amount of interest on account of such indebtedness does not exceed the
usury ceiling from time to time in effect and applicable to such indebtedness
for so long as such indebtedness is outstanding. To the extent federal law
permits Bank to contract for, charge or receive a greater amount of interest,
Bank will rely on federal law instead of the Texas Finance Code, as
supplemented, for the purpose of determining the Maximum Rate. Additionally, to
the maximum extent permitted by applicable law now or hereafter in effect, Bank
may, at its option and from time to time, implement any other method of
computing the Maximum Rate under the Texas Finance Code, as supplemented, or
under other applicable law, by giving notice, if required, to Borrower as
provided by applicable law now or hereafter in effect. Notwithstanding anything
to the contrary contained herein or in any of the other Loan Documents, it is
not the intention of Bank to accelerate the maturity of any interest that has
not accrued at the time of such acceleration or to collect unearned interest at
the time of such acceleration.

      In no event shall Chapter 346 of the Texas Finance Code (which regulates
certain revolving loan accounts and revolving tri-party accounts) apply to this
Note. To the extent that Chapter 303 of the Texas Finance Code, is applicable to
this Note, the "weekly ceiling" specified in such Chapter 303 is the applicable
ceiling; provided that, if any applicable law permits greater interest, the law
permitting the greatest interest shall apply.

      If this Note is placed in the hands of an attorney for collection, or is
collected in whole or in part by suit or through probate, bankruptcy or other
legal proceedings of any kind, Borrower agrees to pay, in addition to all other
sums payable hereunder, all costs and expenses of collection, including but not
limited to reasonable attorneys' fees.

      Borrower and any and all endorsers and guarantors of this Note severally
waive presentment for payment, notice of nonpayment, protest, demand, notice of
protest, notice of intent to accelerate, notice of acceleration and dishonor,
diligence in enforcement and indulgences of every kind and without further
notice hereby agree to renewals, extensions, exchanges or releases of
collateral, taking of additional collateral, indulgences or partial payments,
either before or after maturity.

      Borrower agrees that Bank may provide any information Bank may have about
Borrower or about any matter relating to this Note to BANK ONE CORPORATION, or
any of its subsidiaries or affiliates or their successors, or to any one or more
purchasers or potential purchasers of this Note. Borrower agrees that Bank may
at any time sell, assign or transfer one of more interests or participations in
all or any part of its rights or obligations in this Note to one or more
purchases whether or not related to Bank.

      BORROWER AND BANK (BY ITS ACCEPTANCE HEREOF) HEREBY VOLUNTARILY,
KNOWINGLY, IRREVOCABLY AND UNCONDITIONALLY WAIVE ANY RIGHT TO HAVE A JURY
PARTICIPATE IN RESOLVING ANY DISPUTE (WHETHER BASED UPON CONTRACT, TORT OR
OTHERWISE) BETWEEN BORROWER AND BANK ARISING OUT OF OR IN ANY WAY RELATED TO
THIS NOTE OR THE TRANSACTIONS CONTEMPLATED BY THIS NOTE. THIS PROVISION IS A
MATERIAL INDUCEMENT TO BANK TO PROVIDE THE FINANCING EVIDENCED BY THIS NOTE.

PROMISSORY NOTE

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      THIS NOTE HAS BEEN EXECUTED UNDER, AND SHALL BE CONSTRUED AND ENFORCED IN
ACCORDANCE WITH, THE LAWS OF THE STATE OF TEXAS, EXCEPT AS SUCH LAWS ARE
PREEMPTED BY APPLICABLE FEDERAL LAWS.

                                          BORROWER:

                                          MACE SECURITY PRODUCTS, INC.

                                          By: /s/ Gregory M. Krzemien
                                              -----------------------
                                          Gregory M. Krzemien, Treasurer

PROMISSORY NOTE

                                     PAGE 3<PAGE>

                                                                  EXHIBIT 10.169

                   FIRST AMENDMENT TO ASSET PURCHASE AGREEMENT

      This First Amendment to Asset Purchase Agreement ("Amendment") is made as
of August 27, 2004, by and among Vernex, Inc. ("Company"), and Jin Moon
("Shareholder") on the one hand, and Mace Security Products, Inc., on the other
hand. For purposes of this Agreement, Mace Security Products, Inc. is sometimes
referred to as the "Purchaser," and the Company and the Shareholder are
collectively referred to as the "Sellers."

                                    RECITALS

      The Purchaser and Sellers are parties to an Asset Purchase Agreement dated
September 26, 2003 ("Asset Purchase Agreement"). Purchaser and Sellers have
entered into this Amendment as the wish to agree to a modification of the
certain terms and provisions in the Asset Purchase Agreement.

      Throughout this Amendment, certain terms are capitalized. The capitalized
terms shall have the meanings given to the terms in the Asset Purchase
Agreement, unless otherwise specifically defined in this Amendment.

      Intending to be legally bound and in exchange for the mutual obligations
and benefits set forth in this Amendment, the parties hereto have entered into
this Amendment.

                                    AGREEMENT

      1.    Second Payment. Section 1.3(c) of the Asset Purchase Agreement
provides as follows:

                  "(c) Purchaser shall pay the Company a Second Payment, as
            hereinafter defined. The "Second Payment" shall equal one half of
            (i) the Vernex Revenue, as hereafter defined, less (ii) the Vernex
            Product Cost, as hereafter defined. For purposes of this Paragraph
            1.3(c), the "Vernex Revenue" is the revenue received by Purchaser in
            cash, not subject to return or refund, during the period beginning
            on the Closing Date and ending one year from the Closing Date for
            Products which are sold by Purchaser under the name and label of
            Vernex and for the OEM sale of non-branded CRT and plasma screen
            monitors where M.K. Moon was the procuring salesperson who obtained
            the sale of the Products or OEM monitors ("Vernex Products"). For
            purposes of this Paragraph 1.3(c) the "Vernex Product Cost" shall
            equal the amount paid to the manufacturers of the Vernex Products
            and the OEM CRT and plasma screen monitors which were sold to
            generate the Vernex Revenue and Purchaser's shipping, custom
            clearance and tax costs for those

                                       1
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            Vernex Products, CRT monitors and plasma monitors into Purchaser's
            warehouse. The amount of the Second Payment shall be calculated by
            Purchaser and given to Company for review, no latter then sixty days
            after the one year anniversary date of the Closing Date. Once
            Purchaser and Company agree on the amount of the Second Payment,
            Purchaser shall pay the Second Payment to the Company in twelve
            equal monthly installments. The first installment shall be paid on
            the fifth business day of the month following the month that the
            amount of the Second Payment was determined and the next eleven
            installments shall be paid on the fifth business day of each of the
            following eleven months. The Second Payment shall be made in cash.
            The parties agree that for purposes of computing the Vernex Revenue,
            Products sold by Purchaser under the Mace label and name shall not
            be included in the Vernex Revenue. The parties further agree that
            from the Closing Date to one year after the Closing Date, Purchaser
            shall not sell any Products to the individuals and entities that
            Company was selling Products to under the name and label of Vernex
            prior to the Closing Date, except (i) for Products under the Vernex
            name and label, (ii) non-branded OEM CRT and Plasma monitors, and
            (iii) for Products under the Mace name and label sold to individuals
            and entities which were sold Products by Purchaser under the Mace
            name and label prior to the Closing Date."

Section 1.3(c) of the Asset Purchase Agreement is hereby deleted in it entirety.
As consideration for the Assets in the place of the Second Payment, as set forth
in the deleted Section 1.3(c) of the Asset Purchase Agreement, the parties
hereto agree that within four business days of the execution of this Amendment
Purchaser shall deliver to Sellers Forty Thousand (40,000) shares of Mace
Security International, Inc Common Stock ("MSI Stock"). The MSI Stock shall be
delivered in the name of the Shareholder. The Company agrees to file a plan of
liquidation within one year of the date hereof.

      2.    Common Stock. The MSI Stock to be issued pursuant to this Amendment
has been duly authorized and, when issued, will be validly issued, fully paid
and non-assessable. The MSI Stock delivered to the Sellers as payment, shall be
registered under a shelf registration statement on Form S-4 pursuant to the
Securities Act of 1933 (the "Act"). Purchaser has made available to Sellers all
historical filings made by MSI on Forms 8-K, 10-K, 10-Q and Proxy Statements
timely filed with the Securities and Exchange Commission ("SEC") for fiscal year
ending December 31, 2003, and the fiscal quarter ended March 30, 2004 (the
"Public Reports").

      (a) Sellers acknowledge that they have received and have reviewed the
Public Reports, together with the prospectus prepared from the S-4 registration
statement under which the MSI Stock will be delivered. Sellers acknowledge that
the Public Reports are all available at www.sec.gov/edgar.

      (b) Sellers acknowledge that Purchaser has advised the Sellers that the
MSI Stock when delivered shall have been registered under the Act pursuant to an
S-4 registration statement. The

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Sellers acknowledge that when selling the MSI Stock through a broker they will
have a prospectus delivery requirement. Purchaser will furnish to the Sellers
such number of prospectuses, if required, under the Act, prepared in conformity
with the requirements of the Act, and such other documents as the Sellers may
reasonably request in order to facilitate the public sale or other disposition
of the securities to be sold by the Sellers. A legend in substantially the
following form will be placed on the certificates evidencing the MSI Stock to be
issued to the Sellers:

            "The securities represented by this certificate have been registered
            under the Securities Act of 1933, pursuant to an S-4 registration
            statement. The holder of the certificate is required to deliver a
            prospectus prepared from the registration statement, when trading
            the securities represented by this certificate"

      (c) Notwithstanding anything else herein to the contrary, MSI's obligation
to keep the shelf registration statement continuously effective shall be
suspended during any period that there exists material, non-public information
relating to MSI. MSI shall keep such registration statement current and
effective, until such time as the shares may be sold by the Sellers at any time
pursuant to the provisions of Rule 144 or otherwise without any restrictions,
including restrictions relating to volume, manner of sale, and notice, or until
such earlier date as all of the shares registered pursuant to such registration
statement shall have been sold or otherwise transferred to a third party. MSI
shall also prepare and file with the SEC such amendments and supplements to such
registration statement (and the prospectus used in connection therewith) as may
be necessary to update and keep such registration statement current and
effective for such period and to comply with the provisions of the Act with
respect to the sale of all securities covered by such registration statement.

      3.    Entire Agreement. This Amendment is the final, complete and
exclusive statement and expression of the agreement among the parties hereto
with relation to the subject matter of this Amendment, it being understood that
there are no oral representations, understandings or agreements covering the
same subject matter as the Amendment. The Amendment supersedes, and cannot be
varied, contradicted or supplemented by evidence of any prior to contemporaneous
discussions, correspondence, or oral or written agreements of any kind. The
parties to this Amendment have relied on their own advisors for all legal,
accounting, tax or other advice whatsoever with respect to the Amendment and the
transactions contemplated hereby.

      4.    Counterparts. This Agreement may be executed simultaneously in two
or more counterparts, each of which shall be deemed an original and all of which
together shall constitute but one and the same instrument.

      5.    Notices. All notices or other communications required or permitted
hereunder shall be in writing and may be given by depositing the same in United
States mail, addressed to the party to be notified, postage prepaid and
registered or certified with return receipt requested, by overnight courier or
by delivering the same in person to such party.

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      (a) If to Purchaser, addressed to them at:

             Executive Vice President
             Mace Security International, Inc.
             1000 Crawford Place, Fourth Floor
             Mt. Laurel, NJ 08054

      (b) If to Sellers, addressed to them at:

             M.K. Moon
             13621 Deering Bay Drive No 603
             Coral Gables, Fl 33158

Notice shall be deemed given and effective the day personally delivered, the day
after being sent by overnight courier and five business days after the deposit
in the U.S. mail of a writing addressed as above and sent first class mail,
certified, return receipt requested, or when actually received, if earlier. Any
party may change the address for notice by notifying the other parties of such
change in accordance with this Section 5.

      6.    Governing Law. This Amendment shall be governed by and construed in
accordance with the internal laws of the State of Florida, without giving effect
to any choice or conflict of law provision or rule (whether of the State of
Florida or any other jurisdiction) that would cause the application of the laws
of any jurisdiction other than the State of Florida.

      7.    Provisions of Agreement. All terms and provisions of the Agreement
not modified by this Amendment shall remain unmodified and in full force and
effect as set forth in the Agreement.

      8.    Construction. The parties have participated jointly in the
negotiation and drafting of this Amendment. In the event an ambiguity or
question of intent or interpretation arises, this Amendment shall be construed
as if drafted jointly by the parties and no presumption or burden of proof shall
arise favoring or disfavoring any party by virtue of the authorship of any of
the provisions of this Amendment.

      IN WITNESS WHEREOF, the parties have executed this Agreement on the date
first above written.

      PURCHASER

      MACE SECURITY PRODUCTS, INC.

      By: /s/ Robert M. Kramer
          --------------------
          Robert M. Kramer, Vice President

                                       4
<PAGE>

      COMPANY

      VERNEX, INC.

      By: /s/ M.K. Moon
          -------------
          M.K. Moon, President

      SHAREHOLDER

      /s/ Jin Moon
      ------------
      Jin Moon

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