EXHIBIT 4.3

                                                                         Annex B


                                PENTASAFE, INC.
                           THIRD AMENDED AND RESTATED
                      1998 STOCK PURCHASE AND OPTION PLAN

Section 1. Purpose of Plan

     The purpose of the Third Amended and Restated PentaSafe, Inc. 1998 Stock
Option Plan (the "Plan") is:

     (a) to secure for PentaSafe Security Technologies, Inc., a Texas
corporation (the "Company"), and its shareholders the benefits of the incentive
inherent in the ownership of the common stock of the Company by the directors,
officers and key employees of the Company who will be largely responsible for
the Company's future growth and financial success;

     (b) to promote the long term financial interests and growth of the Company
and its affiliates by attracting and retaining management personnel with the
training, experience and ability to enable them to make a substantial
contribution to the success of the Company's business;

     (c) to motivate management personnel by means of growth-related incentives
to achieve long range goals; and

     (d) to further the alignment of interests of participants with those of the
shareholders of the Company through opportunities for increased stock, or
stock-based, ownership in the Company.

Section 2. Definitions

     As used in the Plan, the following words shall have the following meanings:

     "Affiliate" means, with respect to the Company, any corporation directly or
indirectly controlling, controlled by, or under common control with, the Company
or any other entity designated by the Board of Directors of the Company in which
the Company or an Affiliate has an interest.

     "Board of Directors" means the Board of Directors of the Company.

     "Change of Control" means the occurrence of any of the following events:
(i) any person, entity or group of (as such terms are used in Section 13(d) or
14(d) of the Exchange Act) persons or entities becomes a "beneficial owner" (as
determined pursuant to Rules 13d 3 and 13d 5 promulgated under the Exchange
Act), directly or indirectly, of securities of the Company having 50% or more of
the total voting power of all classes of capital stock of the Company entitled
to vote generally in the election of directors of the Company; (ii) at any time
during any 24 month period, individuals who at the beginning of such period
constituted the Board of Directors (together with any new directors whose
election, or nomination for election by the shareholders of the Company, to the
Board of


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Directors was approved by a majority of the directors then still in office who
either were directors at the beginning of such period or whose election or
nomination for election was previously so approved) cease for any reason to
constitute a majority of the Board of Directors of the Company then in office;
(iii) the Board of Directors approves an agreement providing for the sale,
lease, transfer or other disposition of all or substantially all of the assets
of the Company, in one transaction or a series of related transactions, to any
"person" or "group" (as such terms are used in Section 13(d) of the Exchange
Act) other than a wholly owned subsidiary of the Company; (iv) the Board of
Directors approves an agreement providing for the merger or consolidation of the
Company with another corporation, other than a merger in which the Company would
be the surviving corporation and which would result in (a) securities having 50%
or more of the total voting power of all classes of capital stock entitled to
vote generally in the election of directors of the surviving corporation being
"beneficially owned" (as determined pursuant to Rules 13d 3 and 13d 5 under the
Exchange Act) by the holders of the capital stock of the Company immediately
prior to such merger and (b) no "person" or "group" (as such terms are used in
Section 13(d) of the Exchange Act) "beneficially owning" (as determined pursuant
to Rules 13d 3 and 13d 5 under the Exchange Act), directly or indirectly,
securities having 33% or more of the total voting power of all classes of
capital stock entitled to vote generally in the election of directors of the
surviving corporation; or (v) the Board of Directors approves a plan for the
liquidation or dissolution of the Company.

     "Committee" means the Compensation Committee of the Board of Directors.

     "Common Stock" or "Share" means common stock of the Company, no par value
per share, which may be authorized but unissued, or issued and reacquired.

     "Employee" means (i) a person, including an officer, in the regular
full-time employment of the Company or one of its Affiliates who, in the opinion
of the Committee, is, or is expected to be, primarily responsible for the
management, growth or protection of some part or all of the business of the
Company or (ii) any other consultant, contractor or third person who provides
material services to the Company as determined by the Committee or the Board of
Directors.

     "Exchange Act" means the Securities Exchange Act of 1934, as amended.

     "Fair Market Value" shall mean (i) if on the date as of which Fair Market
Value is being determined the Common Stock is listed on a national securities
exchange or is quoted in the NASDAQ System or the over the counter market, the
last sale price, regular way, of such security on the principal national
securities exchange on which such security is at the time listed, (ii) if there
have been no sales on any such exchange on any day, the average of the highest
bid and lowest asked prices on such exchange at the end of such day, (iii) if on
any day the Common Stock is not so listed, the average of the representative bid
and asked prices quoted in the NASDAQ System as of 4:00 P.M., New York time,
(iv) if on any day the Common Stock is not quoted in the NASDAQ System, the
average of the highest bid and lowest asked prices on such day in the domestic
over the counter market as reported by the National Quotation Bureau,
Incorporated, or


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any similar successor organization, in each such case of clauses (i)-(iv)
averaged over a period of 20 days consisting of the day as of which Fair Market
Value is being determined and the latest 19 consecutive trading days prior to
such day, or (v) if the Common Stock is not publicly traded, then the fair
market value of the Common Stock as determined in good faith by the Committee.

     "Grant" means an award made to a Participant pursuant to the Plan and
described in Section 5, including, without limitation, an award of an Incentive
Stock Option, Stock Option, Stock Appreciation Right, Dividend Equivalent Right,
Restricted Stock, Purchase Stock, Performance Units, Performance Shares or Other
Stock Based Grant or any combination of the foregoing.

     "Grant Agreement" means an agreement between the Company and a Participant
that sets forth the terms, conditions and limitations applicable to a Grant.

     "Participant" means an Employee, director or other person having a unique
relationship with the Company or one of its Affiliates, to whom one or more
Grants have been made and such Grants have not all been forfeited or terminated
under the Plan.

     "Stock-Based Grants" means the collective reference to the grant of Stock
Appreciation Rights, Dividend Equivalent Rights, Restricted Stock, Performance
Units, Performance Shares and Other Stock Based Grants.

     "Stock Options" means the collective reference to "Incentive Stock Options"
and "Other Stock Options".

     "Subsidiary" shall mean any corporation in an unbroken chain of
corporations beginning with the Company if each of the companies, or group of
commonly controlled corporations, other than the last corporation in the
unbroken chain then owns stock possessing 50% or more of the total combined
voting power of all classes of stock in one of the other corporations in such
chain.

Section 3. Administration of Plan

     (a) The Plan shall be administered by the Committee. Except as provided in
Section 4, the members of the Committee shall be eligible to be selected for
Grants under the Plan. The Committee may adopt its own rules of procedure, and
action of a majority of the members of the Committee taken at a meeting, or
action taken without a meeting by unanimous written consent, shall constitute
action by the Committee. The Committee shall have the power to interpret the
Plan and to adopt such rules (the "Plan Rules") for the administration,
interpretation and application of the Plan as are consistent herewith and to
interpret or revoke any such rules. All actions taken and all interpretations
and determinations made by the Committee shall be final and binding upon the
Participant, the Company and all other interested persons. No member of the
Committee shall be personally liable for any action, determination or
interpretation made in good faith with respect to the Plan or any Grant. In its
absolute discretion, the Board of Directors may at any time and from time to
time exercise any and all rights and duties of the Committee under the Plan and
the Grant Agreement.


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     (b) The Committee may delegate to the President and to other senior
officers of the Company its duties under the Plan subject to such conditions and
limitations as the Committee shall prescribe, except that only the Committee may
designate and make Grants to Participants who are subject to Section 16 of the
Exchange Act.

     (c) The Committee may employ attorneys, consultants, accountants,
appraisers, brokers or other persons. The Committee, the Company, and the
officers and directors of the Company shall be entitled to rely upon the advice,
opinions or valuations of any such persons. All actions taken and all
interpretations and determinations made by the Committee in good faith shall be
final and binding upon all Participants, the Company and all other interested
persons. No member of the Committee shall be personally liable for any action,
determination or interpretation made in good faith with respect to the Plan or
the Grants, and all members of the Committee shall be fully protected by the
Company with respect to any such action, determination or interpretation.

Section 4. Eligibility

     The Committee may from time to time make Grants under the Plan to such
Employees, directors or other persons having a unique relationship with the
Company or any of its Affiliates, and in such form and having such terms,
conditions and limitations as the Committee may determine. Grants may be granted
singly, in combination or in tandem. The terms, conditions and limitations of
each Grant under the Plan shall be set forth in a Grant Agreement, in a form
approved by the Committee, consistent, however, with the terms of the Plan.

Section 5. Grants

     From time to time, the Committee will determine the forms and amounts of
Grants for Participants. Such Grants may take the following forms in the
Committee's sole discretion:

     (a) Incentive Stock Options - "Incentive Stock Options" are stock options
within the meaning of Section 422 of the Internal Revenue Code of 1986, as
amended ("Code"), to purchase Common Stock. In addition to other restrictions
contained in the Plan, an option granted under this Section 5(a), (i) may not be
exercised more than 10 years after the date it is granted, (ii) may not have an
option price less than the Fair Market Value of Common Stock on the date the
option is granted, (iii) must otherwise comply with Code Section 422, and (iv)
must be designated as an "Incentive Stock Option" by the Committee. The maximum
aggregate Fair Market Value of Common Stock (determined at the time of each
Grant) with respect to which Incentive Stock Options are first exercisable with
respect to any Participant under this Plan and any Incentive Stock Options
granted to the Participant in any calendar year under any plans of the Company
or any Subsidiary in any such year is $100,000. Payment of the option price
shall be made in accordance with the terms of Section 6, the Grant Agreement and
any applicable Plan Rules in effect at the time.


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     (b) Other Stock Options - "Other Stock Options" are options to purchase
Common Stock which are not designated by the Committee as "Incentive Stock
Options". At the time of the Grant the Committee shall determine, and shall
include in the Grant Agreement or the Plan Rules, the option exercise period,
the option price, and such other conditions or restrictions on the grant or
exercise of the option as the Committee deems appropriate, which may include the
requirement that the grant of options is predicated on the acquisition of
Purchase Shares under Section 5(e) by the Optionee. In addition to other
restrictions contained in the Plan, an option granted under this Section 5(b),
(i) may not be exercised more than 10 years after the date it is granted and
(ii) may not have an option exercise price less than 50% of the Fair Market
Value of Common Stock on the date the option is granted. Payment of the option
price shall be made in accordance with the terms of Section 6, the Grant
Agreement and any applicable Plan Rules in effect at the time.

     (c) Stock Appreciation Rights - "Stock Appreciation Rights" are rights that
upon exercise entitle the holder to receive cash or stock having a value equal
to the excess of (i) the Fair Market Value of a share of Common Stock on the
date of exercise over (ii) the Fair Market Value on the date of Grant (the "Base
Value") multiplied by (iii) the number of rights exercised as determined by the
Committee. Stock Appreciation Rights granted under the Plan may, but need not
be, granted in conjunction with a Stock Option under Section 5(a) or 5(b). The
Committee, in the Grant Agreement or by the Plan Rules, may impose such
conditions or restrictions on the exercise of Stock Appreciation Rights as it
deems appropriate.

     (d) Restricted Stock - "Restricted Stock" is Common Stock delivered to a
Participant with or without payment of consideration with such restrictions or
conditions on the Participant's right to transfer or sell such stock as the
Committee shall determine; provided that the price of any Restricted Stock
delivered for consideration and not as bonus stock may not be less than 50% of
the Fair Market Value of Common Stock on the date such Restricted Stock is
granted or the price of such Restricted Stock may be the par value. Dividends
payable on Restricted Stock may be paid in additional shares of Restricted Stock
equal to the cash dividend payable on the Restricted Stock if a Participant
irrevocably elects so in writing in the calendar year preceding the Grant of
such Restricted Stock. The number of shares of Restricted Stock and the
restrictions or conditions on such shares shall be as the Committee determines,
in the Grant Agreement or by the Plan Rules, and the certificate for the
Restricted Stock shall bear evidence of the restrictions or conditions. No
Restricted Stock may have a restriction period of less than 6 months, other than
in the case of death or disability.

     (e) Purchase Stock - "Purchase Stock" is Common Stock that is offered to a
Participant at such price as determined by the Committee, the acquisition of
which will make him eligible to receive under the Plan, including, but not
limited to, Other Stock Options; provided, however, that the price of such
Purchase Shares may not be less than 50% of the Fair Market Value of the Common
Stock on the date such shares of Purchase Stock are offered.


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     (f) Dividend Equivalent Rights - "Dividend Equivalent Rights" are rights to
receive cash payments from the Company at the same time and in the same amount
as any cash dividends paid on an equal number of shares of Common Stock to
shareholders of record during the period such rights are effective. The
Committee, in the Grant Agreement or by the Plan Rules, may impose such
restrictions and conditions on the Dividend Equivalent Rights, including the
date such rights will terminate, as it deems appropriate, and may terminate,
amend, or suspend such Dividend Equivalent Rights at any time.

     (g) Performance Units - "Performance Units" are rights to receive at a
future date payment in cash of an amount equal to all or a portion of the value
of a unit granted by the Committee. At the time of the Grant, in the Grant
Agreement or by the Plan Rules, the Committee shall determine the base value of
the unit, the performance factors applicable to the determination of the
ultimate payment value of the unit and the period over which such performance
factors will be measured. These factors must include a minimum performance
standard for the Company below which no payment will be made and a maximum
performance level above which no increased payment will be made. The term over
which the Company's performance will be measured shall be not less than six
months.

     (h) Performance Shares - "Performance Shares" are rights to receive at a
future date payment in cash or Common Stock, as determined by the Committee, of
an amount equal to all or a portion of the average Fair Market Value for all
days that the Common Stock is traded during the last forty-five (45) days of the
specified period of performance of a specified number of shares of Common Stock
at the end of a specified period based on such performance factors during the
period. At the time of the Grant, the Committee, in the Grant Agreement or by
the Plan Rules, will determine the factors which will govern the portion of the
rights so payable and the period over which the Company's performance will be
measured. The factors will be based on the Company's performance and must
include a minimum performance standard for the Company below which no payment
will be made and a maximum performance level above which no increased payment
will be made. The term over which the Company's performance will be measured
shall be not less than six months. Performance Shares may be granted for no
consideration.

     (i) Other Stock-Based Grants - The Committee may make other Grants under
the Plan pursuant to which shares of Common Stock (which may, but need not, be
shares of Restricted Stock pursuant to Section 5(d)) or other equity securities
of the Company are or may in the future be acquired, or Grants denominated in
stock units, including ones valued using measures other than market value. Other
Stock-Based Grants may be granted with or without consideration; provided,
however, that the price of any such Grant made for consideration that provides
for the acquisition of shares of Common Stock or other equity securities of the
Company may not be less than 50% of the Fair Market Value of the Common Stock or
such other equity securities on the date of grant of such Grant. Such Other
Stock-Based Grants may be made alone, in addition to or in tandem with any Grant
of any type made under the Plan and must be consistent with the purposes of the
Plan.


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Section 6. Payment of Option Price for Stock Options

     The payment of the option price for all shares purchased pursuant to the
exercise of Stock Options shall be (w) by cash or check in full on the date of
exercise (such cash or check may be delivered on behalf of a Participant by a
stock broker designated by the Company to whom the Participant has submitted an
irrevocable notice of election, on forms approved by the Company, to sell shares
of Common Stock deliverable upon exercise of a Stock Option), (x) through the
delivery of shares of Common Stock having a Fair Market Value equal to the full
amount of the exercise price, (y) by the withholding by the Company from the
shares of Common Stock issuable upon any exercise of the option that number of
shares having a Fair Market Value equal to such exercise price pursuant to a
written election delivered to the Committee prior to the date of exercise, or
(z) by a combination of such methods. The Committee shall determine acceptable
methods for tendering Common Stock and may impose such limitations and
prohibitions on the use of Common Stock to exercise a Stock Option as it deems
appropriate.

Section 7. Limitations and Conditions

     (a) The number of Shares available for Grants under this Plan shall be
1,374,274 shares of the authorized Common Stock as of August 1, 1999, subject to
adjustment in accordance with Section 9 or 10 hereof. The number of Shares
subject to Grants under this Plan to any one Participant shall not be more than
750,000 shares, subject to adjustment in accordance with Section 9 or 10 hereof.
Unless restricted by applicable law, Shares related to Grants that are
forfeited, terminated, cancelled or expire unexercised, shall immediately become
available for Grants.

     (b) No Grants shall be made under the Plan beyond ten years after the
effective date of the Plan, but the terms of Grants made on or before the
expiration of the Plan may extend beyond such expiration. At the time a Grant is
made or amended or the terms or conditions of a Grant are changed, the Committee
may provide for such limitations or conditions on such Grant as the Committee in
its sole discretion may determine; provided that such limitations or conditions
are set forth in writing in the Participant's Grant Agreement.

     (c) Nothing contained herein shall affect the right of the Company to
terminate any Participant's employment at any time or for any reason, with or
without cause.

     (d) Deferrals of Grant payouts may be provided for, at the sole discretion
of the Committee, in the Grant Agreements.

     (e) Except as otherwise prescribed by the Committee, the amounts of the
Grants for any employee of an Affiliate, along with interest, dividend, and
other expenses accrued on deferred Grants, shall be charged to the Participant's
employer during the period for which the Grant is made. If the Participant is
employed by more than one Affiliate or by both the Company and an Affiliate
during the period for which the Grant


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is made, the Participant's Grant and related expenses will be allocated between
the companies employing the Participant in a manner prescribed by the Committee.

     (f) Other than as specifically provided with regard to the death of a
Participant, no benefit under the Plan shall be subject in any manner to
anticipation, alienation, sale, transfer, assignment, pledge, encumbrance, or
charge, and any attempt to do so shall be void. No such benefit shall, prior to
receipt thereof by the Participant, be in any manner liable for or subject to
the debts, contracts, liabilities, engagements, or torts of the Participant.

     (g) Participants shall not be, and shall not have any of the rights or
privileges of, shareholders of the Company in respect of any Shares purchasable
in connection with any Grant unless and until certificates representing any such
Shares have been issued by the Company to such Participants in accordance with
the terms and procedures governing the exercise of any Grant set forth in the
Participant's Grant Agreement. The issuance of any Shares in connection with the
exercise of a Grant may, in the sole and absolute discretion of the Company, be
made contingent upon and subject to the Participant entering into a written
agreement with the Company regarding the rights and obligations of the
Participant as a stockholder of the Company.

     (h) No election as to benefits or exercise of Stock Options, Stock
Appreciation Rights, or other rights may be made during a Participant's lifetime
by anyone other than the Participant except by a legal representative appointed
for or by the Participant.

     (i) Absent express provisions to the contrary, any Grant under this Plan
shall not be deemed compensation for purposes of computing benefits or
contributions under any retirement plan of the Company or its Subsidiaries and
shall not affect any benefits under any other benefit plan of any kind now or
subsequently in effect under which the availability or amount of benefits is
related to level of compensation. This Plan is not a "Retirement Plan" or
"Welfare Plan" under the Employee Retirement Income Security Act of 1974, as
amended.

     (j) Unless the Committee determines otherwise, no benefit or promise under
the Plan shall be secured by any specific assets of the Company or any of its
Subsidiaries, nor shall any assets of the Company or any of its Subsidiaries be
designated as attributable or allocated to the satisfaction of the Company's
obligations under the Plan.

Section 8. Transfers and Leaves of Absence

     For purposes of the Plan, unless the Committee determines otherwise: (a) a
transfer of a Participant's employment without an intervening period of
separation among the Company and any Affiliate shall not be deemed a termination
of employment, and (b) a Participant who is granted in writing a leave of
absence shall be deemed to have remained in the employ of the Company during
such leave of absence.


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Section 9. Adjustments

     In the event of any change in the outstanding Common Stock by reason of a
stock split, spin-off, stock dividend, stock combination or reclassification,
recapitalization or merger, Change of Control or similar event, or as required
under any Grant Agreement, the Committee may adjust appropriately the number of
Shares subject to the Plan and available for or covered by Grants and Share
prices related to outstanding Grants and make such other revisions to
outstanding Grants as it deems are equitably required.

Section 10. Merger, Consolidation, Exchange, Acquisition, Liquidation or
            Dissolution

     In its absolute discretion, and on such terms and conditions as it deems
appropriate, coincident with or after the grant of any Stock Option or any
Stock-Based Grant, the Committee may provide, with respect to the merger or
consolidation of the Company into another corporation, the exchange of all or
substantially all of the assets of the Company for the securities of another
corporation, a Change of Control or the recapitalization, reclassification,
liquidation or dissolution of the Company, either (i) that such Stock Option or
Stock-Based Grant cannot be exercised after such event, in which case the
Committee shall also provide, either by the terms of such Stock Option or
Stock-Based Grant or by a resolution adopted prior to the occurrence of such
event, that for some period of time prior to such event, such Stock Option or
Stock-Based Grant shall be exercisable as to all shares subject thereto which
are exercisable or, by virtue of the event, become exercisable, notwithstanding
anything to the contrary herein (but subject to the provisions of Section 7(b))
and that, upon the occurrence of such event, such Stock Option or Stock-Based
Grant shall terminate and be of no further force or effect; or (ii) that even if
the Stock Option or Stock-Based Grant shall remain exercisable after such event,
from and after such event, any such Stock Option or Stock- Based Grant shall be
exercisable only for the kind and amount of securities and/or other property, or
the cash equivalent thereof, receivable as a result of such event by the holder
of a number of shares of stock for which such Stock Option or Stock-Based Grant
could have been exercised immediately prior to such event.

     In addition, in the event of a Change of Control, the Committee may, in its
absolute discretion and on such terms and conditions as it deems appropriate,
provide, either by the terms of such Stock Option or Stock-Based Grant or by a
resolution adopted prior to the occurrence of the Change of Control, that such
Stock Option or Stock-Based Grant shall be exercisable as to all or any portion
of the shares subject thereto, notwithstanding anything to the contrary herein
(but subject to the provisions of Section 7(b)).

Section 11. Amendment and Termination

     The Committee shall have the authority to make such amendments to any terms
and conditions applicable to outstanding Grants as are consistent with this
Plan; provided that, except for adjustments under Section 9 or 10 hereof, no
such action shall modify such Grant in a manner adverse to the Participant
without the Participant's consent except


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as such modification is provided for or contemplated in the terms of the Grant.
The Board of Directors may amend, suspend or terminate the Plan.

Section 12. Withholding Taxes

     The Company shall have the right to deduct from any cash payment made under
the Plan any federal, state or local income or other taxes required by law to be
withheld with respect to such payment. It shall be a condition to the obligation
of the Company to deliver shares upon the exercise of a Stock Option or Stock
Appreciation Right, upon payment of Performance Units or Performance Shares,
upon delivery of Restricted Stock or upon exercise, settlement or payment of any
Other Stock-Based Grant that the Participant pay to the Company such amount as
may be requested by the Company for the purpose of satisfying any liability for
such withholding taxes. Any Grant Agreement may provide that the Participant may
elect, in accordance with any conditions set forth in such Grant Agreement, to
pay a portion or all of such withholding taxes in shares of Common Stock.

Section 13. Effective Date and Termination Dates

     The Plan shall be effective on and as of the date of its approval by the
shareholders of the Company and shall terminate ten years later, subject to
earlier termination by the Board of Directors pursuant to Section 11; provided,
however, that any payment under the Plan which would constitute a "parachute
payment" under section 280G of the Code must be approved by a vote of 75% of the
Company's shareholders to be effective.


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