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                                                                   EXHIBIT 10.28


                         THERMADYNE HOLDINGS CORPORATION
                            DIRECT INVESTMENT PROGRAM


         SECTION 1. Purpose. The purpose of the Thermadyne Holdings Corporation
Direct Investment Program is to promote the interests of Thermadyne Holdings
Corporation (the "COMPANY") and its stockholders by (i) attracting and retaining
exceptional executive personnel and other key officers and employees of the
Company and its Subsidiaries; (ii) motivating such individuals by means of an
equity-based incentive to achieve longer-range performance goals; and (iii)
enabling such individuals to participate in the long-term growth and financial
success of the Company.

         SECTION 2. Definitions. As used in the Plan, the following terms shall
have the meanings set forth below:

         "ALLOCABLE INTEREST" means, as of any date with respect to any unvested
Coinvestment Shares that have been pledged by a Participant as security for a
Loan, the following product:

                                  0.68 x I x F,

where I is the total interest accrued through such date on all Loans for which
such unvested Coinvestment Shares are so pledged, and F is a fraction the
numerator of which is the number of such unvested Coinvestment Shares and the
denominator of which is the total number of Coinvestment Shares that have been
pledged by the Participant as security for such Loans.

         "AFFILIATE" means (i) any entity that is, directly or indirectly,
controlled by the Company and (ii) any other entity in which the Company has a
significant equity interest or which has a significant equity interest in the
Company, in either case as determined by the Committee.

         "BOARD" shall mean the Board of Directors of the Company.

         "CAUSE" means (i) dishonesty by a Participant that results in
substantial personal enrichment at the expense of the Company or (ii)
demonstratively willful repeated violations of a Participant's obligations to
the Company (including under any employment agreement between the Participant
and the Company) which are intended to result in material injury to the Company.

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         "CHANGE OF CONTROL" means:

                  (a) any "person" (as such term is used in Section 3(a)(9) and
         13(d)(3) of the Exchange Act) other than (A) the DLJ Entities and/or
         their respective Permitted Transferees (as defined in the Investors'
         Agreement) or (B) any "group" (within the meaning of such Section
         13(d)(3)) of which the DLJ Entities constitute a majority (on the basis
         of ownership interest), acquires, directly or indirectly, by virtue of
         the consummation of any purchase, merger or other combination,
         securities of the Company representing more than 51% of the combined
         voting power of the Company's then outstanding voting securities with
         respect to matters submitted to a vote of the stockholders generally;
         or

                  (b) a sale or transfer by the Company or any of its
         Subsidiaries of substantially all of the consolidated assets of the
         Company and its Subsidiaries to an entity which is not an Affiliate of
         the Company prior to such sale or transfer.

         "CODE" means the Internal Revenue Code of 1986, as amended from time to
time.

         "COINVESTMENT SHARES" means Shares of the Company purchased under the
Plan and designated as Coinvestment Shares.

         "COMMITTEE" means a committee of the Board designated by the Board to
administer the Plan and composed of not less than the minimum number of persons
from time to time required by Rule 16b-3, each of whom, to the extent necessary
to comply with Rule 16b-3 only, is a "Non-Employee Director" within the meaning
of Rule 16b-3. Until otherwise determined by the Board, the full Board shall be
the Committee under the Plan.

         "EMPLOYEE" means an employee of the Company or any Subsidiary.

         "EXCHANGE ACT" shall mean the Securities Exchange Act of 1934, as
amended.

         "FAIR MARKET VALUE" means with respect to the Shares, as of the
consummation of the merger of the Company and Mercury Acquisition Corporation,
$34.50 per share, and as of any other given date or dates, the average reported
closing price of a share of such class of common stock on such exchange or
market as is the principal trading market for such class of common stock for the
three trading days immediately preceding such date or dates. If such class of
common stock is not traded on an exchange or principal trading market on such



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date, the Fair Market Value of a Share shall be determined by the Committee in
good faith taking into account as appropriate recent sales of the Shares, recent
valuations of the Shares and such other factors as the Committee shall in its
discretion deem relevant or appropriate; provided, that if Fair Market Value is
to be determined in connection with the exercise by the Company or a Participant
of a right under this Plan or a Purchase Agreement to purchase, or cause to be
purchased by the Company, 40,000 or more Shares, the Fair Market Value of a
Share shall be the value selected by an unaffiliated financial institution
designated by the Committee (subject to the reasonable approval of the
Participant) as most accurately reflecting the value of a Share, from among
sealed proposed valuations submitted to such institution by each of such
Participant and the Company.

         "INVESTORS' AGREEMENT" means the Investors' Agreement dated as of May
22, 1998 among (i) the Company, (ii) DLJ Merchant Banking Partners II, L.P., DLJ
Offshore Partners II, C.V., DLJ Merchant Banking Partners II-A, L.P., DLJ
Diversified Partners, L.P., DLJ Diversified Partners-A, L.P., DLJ Millennium
Partners, L.P., DLJ Millennium Partners-A, L.P., DLJMB Funding II, Inc., UK
Investment Plan 1997 Partners, DLJ EAB Partners, L.P., DLJ First ESC, L.P. and
DLJ ESC II, L.P. (collectively, the "DLJ ENTITIES") and (iii) certain other
Persons listed on the signature pages thereof.

         "LOAN" shall have the meaning set forth in Section 5(c).

         "PARTICIPANT" means the individuals listed on Exhibit A hereto (and to
the extent applicable, any heirs, legatees or legal representatives thereof).

         "PERMITTED TRANSFEREE" shall have the meaning assigned to such term in
the Investors' Agreement.

         "PERSON" means any individual, corporation, limited liability company,
partnership, association, joint-stock company, trust, unincorporated
organization, government or political subdivision thereof or other entity.

         "PLAN" means this Thermadyne Holdings Corporation Direct Investment
Program.

         "PLAN SHARES" means any Coinvestment Shares or Reinvestment Shares
purchased by a Participant under this Plan.

         "PURCHASE AGREEMENT" shall mean an agreement to be executed by the
Company and a Participant as a condition to the acquisition of Shares under the
Plan by such Participant.



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         "PURCHASE PRICE" shall have the meaning set forth in Section 5(b).

         "REINVESTMENT SHARES" means Shares of the Company purchased under the
Plan and designated as Reinvestment Shares.

         "RULE 16b-3" shall mean Rule 16b-3 as promulgated and interpreted by
the SEC under the Exchange Act, or any successor rule or regulation thereunder
as in effect from time to time.

         "SEC" shall mean the Securities and Exchange Commission or any
successor thereto.

         "SHARES" means shares of common stock, $0.01 par value, of the Company
or such other securities as may be designated by the Committee from time to
time.

         "SUBSIDIARY" shall mean, with respect to any Person, any corporation or
other entity of which securities or other ownership interests having ordinary
voting power to elect a majority of the board of directors or other persons
performing similar functions are at the time directly or indirectly owned by
such Person.

         SECTION 3. Administration.

         (a) Authority of Committee. The Plan shall be administered by the
Committee or by the Board as a whole, if no Committee has been constituted. All
references to the powers and responsibilities of the Committee set forth in this
Plan shall be deemed to be references to the Board if no Committee has been
constituted. Subject to the terms of the Plan, applicable law and contractual
restrictions affecting the Company, and in addition to other express powers and
authorizations conferred on the Committee by the Plan, the Committee shall have
full power and authority to: (i) determine whether, to what extent, and under
what circumstances Purchase Agreements may be amended or terminated and Shares
acquired thereunder may be reacquired or transferred; (ii) interpret and
administer the Plan and any Purchase Agreement or other instrument or agreement
relating to, or made under, the Plan; (iii) establish, amend, suspend, or waive
such rules and regulations and appoint such agents as it shall deem appropriate
for the proper administration of the Plan; and (iv) make any other determination
and take any other action that the Committee deems necessary or desirable for
the administration of the Plan.

         (b) Committee Discretion Binding. Unless otherwise expressly provided
in the Plan, all designations, determinations, interpretations, and other
decisions



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under or with respect to the Plan or any Purchase Agreement shall be within the
sole discretion of the Committee, may be made at any time and shall be final,
conclusive and binding upon all Persons, including the Company, any Subsidiary,
any Participant, any holder or beneficiary of any Purchase Agreement, any
shareholder and any Employee.

         SECTION 4. Shares Available for Purchase under Plan.

         (a) Number of Shares. Subject to adjustment as provided in Section
4(b), the number of Shares available for purchase under the Plan shall be
141,002, of which 70,501 Shares shall be designated as Reinvestment Shares and
70,501 Shares shall be designated as Coinvestment Shares.

         (b) Adjustments. In the event that the Committee determines that any
dividend or other distribution (whether in the form of cash, Shares, other
securities or other property), recapitalization, stock split, reverse stock
split, reorganization, reclassification, merger, consolidation, split-up,
spin-off, combination, repurchase, or exchange of Shares or other securities of
the Company, issuance of warrants or other rights to purchase Shares or other
securities of the Company, or other similar corporate transaction or event
affects the Shares such that an adjustment is determined by the Committee to be
appropriate in order to prevent dilution or enlargement of the benefits or
potential benefits of a Participant's investment in Shares under the Plan, then
the Committee shall, in such manner as it deems equitable, make such
adjustments, if any, to the number and kind of Shares (or number and kind of
other securities or property) with respect to which Purchase Agreements have
been or may thereafter be entered into hereunder as it deems appropriate and
necessary. Notwithstanding the foregoing, the issuance of warrants by the
Company in connection with the merger of the Company and Mercury Acquisition
Corporation shall not give rise to any such adjustment.

         (c) Sources of Shares. Any Shares delivered pursuant to a Purchase
Agreement may be either authorized and unissued shares, or previously issued
shares, held in the treasury of the Company.

         SECTION 5. Share Purchases.

         (a) Purchase. The number of Coinvestment and Reinvestment Shares set
forth opposite each Participant's name in Exhibit A hereto shall be made
available for purchase by such Participant, effective as of the consummation of
the merger of the Company and Mercury Acquisition Corporation.



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         (b) Purchase Price. The price at which each Share under the Plan may be
purchased by a Participant hereunder (the "PURCHASE PRICE") shall be the Fair
Market Value as of the date of purchase.

         (c) Payment. No Shares shall be delivered hereunder until payment in
full of the Purchase Price therefor is received by the Company. Such payment may
be made in cash or its equivalent, pursuant to financing arrangements approved
by the Committee, including loans to Participants made by the Company in the
form of Exhibit B hereto (the "LOANS") of up to the amounts set forth opposite
such Participants' names in Exhibit A hereto, or a combination of the foregoing,
provided that the combined value of all cash, cash equivalents and such
financing arrangements is at least equal to such Purchase Price.

         SECTION 6. Vesting.

         (a) Of the Coinvestment Shares purchased by any Participant, 20% shall
vest on each of the first five anniversaries of the date of purchase, provided
such Participant is employed by the Company or its Subsidiary as of such
anniversary.

         (b) Upon the occurrence of a Change of Control, all Coinvestment Shares
that have not yet vested and that are held by a Participant who is then in the
employ of the Company or its Subsidiary, or that are held by the Permitted
Transferee of such a Participant, shall immediately become vested in full.

         (c) All Reinvestment Shares shall be fully vested as of the date of
purchase by the Participant hereunder.

         SECTION 7. Termination of Employment; Repayment of Loan. Except as may
be set forth in any Purchase Agreement or as otherwise determined by the
Committee at any time, upon the termination of a Participant's employment with
the Company and its Subsidiaries:

         (a) Any outstanding Loan shall become due in accordance with the terms
of such Loan.

         (b) In the event of a Participant's termination of employment other
than by the Company or its Subsidiary for Cause and other than by reason of the
Participant's death, the Company or its designee shall have the right to
purchase all or a portion of the Plan Shares held by the Participant or his or
her Permitted Transferee, at a price per Share equal to:

                  (i) In the case of unvested Coinvestment Shares, the lesser of
         (A) the sum of the Purchase Price and the Allocable Interest with
         respect



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         to such unvested Coinvestment Shares and (B) the Fair Market Value of
         such Shares on the date of purchase by the Company; and

                  (ii) In the case of all other Plan Shares, the Fair Market
         Value of such Shares on the date of purchase by the Company.

         (c) In the event of a Participant's termination of employment by reason
of the Participant's death:

                  (i) The Company or its designee shall have the right to
         purchase all or a portion of the unvested Coinvestment Shares held by
         the Participant or his or her Permitted Transferee, at a price per
         Share equal to the lesser of (A) the sum of the Purchase Price and the
         Allocable Interest with respect to such unvested Coinvestment Shares
         and (B) the Fair Market Value of such unvested Coinvestment Shares on
         the date of purchase by the Company;

                  (ii) The Participant's estate or Permitted Transferee shall
         have the right to cause the Company to purchase all or a portion of the
         Reinvestment Shares and vested Coinvestment Shares held by the
         Participant or his or her Permitted Transferee, at a price per Share
         equal to the Fair Market Value of such Shares on the date of purchase
         by the Company; and

                  (iii) In the event, after the Participant's death, of maturity
         of any Loan secured by the Reinvestment Shares and vested Coinvestment
         Shares held by the Participant's estate or Permitted Transferee, the
         Company or its designee shall have the right to purchase all or a
         portion of such Shares, at a price per Share equal to the Fair Market
         Value of such Shares on the date of purchase by the Company.

         (d) In the event of a Participant's termination of employment by the
Company or its Subsidiary for Cause, the Company or its designee shall have the
right to purchase all or a portion of the Plan Shares held by the Participant or
his or her Permitted Transferee, at a price per Share equal to:

                  (i) In the case of Coinvestment Shares (whether or not
         vested), the lesser of (A) the Purchase Price with respect to such
         Shares and (B) the Fair Market Value of such Shares on the date of
         purchase by the Company; and

                  (ii) In the case of Reinvestment Shares, the Fair Market Value
         of such Shares on the date of purchase by the Company.



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         (e) If either the Company or, in the case of Section 7(c)(ii), a
Participant's estate or Permitted Transferee, elects to exercise their rights
under this Section 7, the Company or such estate or Permitted Transferee, as the
case may be, shall deliver written notice (a "PURCHASE NOTICE") to the other to
such effect:

                  (i) in the case of any purchase pursuant to Sections 7(c)(ii)
         or 7(c)(iii), prior to the third business day before the maturity date
         of any Loan secured by the Plan Shares to be so purchased; and

                  (ii) in the case of any other purchase under this Section 7,
         at any time within the discretion of the Company.

For purposes of this Section 7, the "date of purchase" shall mean the third
business day following the receipt of a Purchase Notice by the other party. The
proceeds of any Shares purchased from a Participant (or his or her Permitted
Transferee) pursuant to this Section 7 shall be applied first to the amount of
any interest and principal outstanding under any Loans held by such Participant
and secured by such Shares, in accordance with the terms of such Loans. Any
excess proceeds remaining after repayment of all such interest and principal
shall be paid to such Participant or his or her Permitted Transferee in cash or
by certified check; provided that if the terms of any agreement to which the
Company is a party, or any of the indentures governing any debt securities
issued by the Company or any of its Subsidiaries would prohibit the Company from
effecting such payment, payment may be effected (to the extent permitted under
such agreement or indenture) through a promissory note having such commercially
reasonable terms and interest rate as may be determined by the Company in its
reasonable discretion; and provided further that in any event such note shall
become due at such time as the prohibitions described above shall lapse.

         SECTION 8. Loan Maturity Prior to Termination of Employment.

         (a) In the event an outstanding Loan becomes due prior to the
termination of the applicable Participant's employment, the Participant shall
have the right to cause the Company to purchase that portion of such
Participant's vested Plan Shares necessary to repay the principal amount of the
Loan and any interest thereon at a per share price equal to such Shares' Fair
Market Value on the date of purchase by the Company.

         (b) If a Participant elects to exercise his or her rights under this
Section 8, the Participant shall deliver a Purchase Notice to the Company to
such effect prior to the third business day before the maturity date of the
applicable Loan.



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The purchase price for such Shares shall be applied and paid in the manner set
forth in Section 7(e).

         SECTION 9. Investors' Agreement. A Participant shall, as a condition
precedent to the purchase of Shares, execute an instrument agreeing to be bound
by the terms of the Investors' Agreement or, at the election of the Company, a
counterpart of the Investors' Agreement. In any event, any Shares shall be
subject to the provisions in the Investors' Agreement regarding restrictions on
transfer and the Company's rights to compel sales and repurchase Shares.

         SECTION 10. Amendment and Termination.

         (a) Amendments to and Termination of the Plan. Unless the Plan shall
theretofore have been terminated as hereinafter provided, the Plan shall
terminate on, and no Purchase Agreement shall be entered into thereunder after,
May 22, 2008. Subject to any contractual restrictions affecting the Company, the
Board may amend, alter, suspend, discontinue, or terminate the Plan or any
portion thereof at any time; provided that no such amendment, alteration,
suspension, discontinuation or termination shall be made without shareholder
approval if such approval is necessary to comply with any tax or regulatory
requirement for which or with which the Board deems it necessary or desirable to
qualify or comply.

         (b) Amendments to Purchase Agreements. The Committee may waive any
conditions or rights under, amend any terms of, or alter, suspend, discontinue,
cancel or terminate, any Purchase Agreement, prospectively or retroactively;
provided that any such waiver, amendment, alteration, suspension,
discontinuance, cancellation or termination that would adversely affect the
rights of any Participant under any Purchase Agreement shall not to that extent
be effective without the consent of the affected Participant.

         SECTION 11. General Provisions.

         (a) No Rights to Participation. No Employee, Participant or other
Person shall have any claim to be granted the opportunity to purchase any Shares
hereunder, and there is no obligation for uniformity of treatment of Employees
or Participants. The terms and conditions of Purchase Agreements need not be the
same with respect to each recipient.

         (b) Share Certificates. Certificates issued in respect of Shares shall,
unless the Committee otherwise determines, be registered in the name of the
Participant or its Permitted Transferees and, so long as a Participant continues
to be governed by the provisions of any Loan, shall be deposited by such
Participant or Permitted Transferee, together with a stock power endorsed in
blank, with the



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Company. When the Participant ceases to be bound by the provisions of the
Investors' Agreement and any Loan, the Company shall deliver such certificates
to the Participant upon request. Such stock certificate shall carry such
appropriate legends, and such written instructions shall be given to the
Company's transfer agent, as may be deemed necessary or advisable by counsel to
the Company in order to comply with the requirements of (i) the Securities Act
of 1933, any state securities laws or any other applicable laws, (ii) the
Investors' Agreement and (iii) any Loan. Subject to the provisions of the
Investors' Agreement, all certificates for Shares or other securities of the
Company or any Affiliate delivered under the Plan pursuant to any Purchase
Agreement shall be subject to such stop transfer orders and other restrictions
as the Committee may deem advisable under the Plan, the applicable Purchase
Agreement or the rules, regulations and other requirements of the SEC or any
stock exchange upon which such Shares or other securities are then listed and
any applicable laws or rules or regulations.

         (c) Execution of Purchase Agreement: Disposition of Shares. No Shares
shall be issued hereunder unless and until a Purchase Agreement shall be
executed by the Company and the Participant.

         (d) No Limit on Compensation Arrangements. Nothing contained in the
Plan shall prevent the Company or any Subsidiary from adopting or continuing in
effect compensation arrangements, which may, but need not, provide for the grant
of options, restricted stock, Shares and other types of awards (subject to
shareholder approval if such approval is required), and such arrangements may be
either generally applicable or applicable only in specific cases.

         (e) No Rights to Employment. Nothing in this Plan or in any Purchase
Agreement shall confer on any individual any right to continue in the employ of
the Company or any Subsidiary of the Company or interfere in any way with the
right of the Company or any Subsidiary of the Company to terminate his or her
employment at any time.

         (f) Governing Law. The validity, construction, and effect of the Plan
and any rules and regulations relating to the Plan and any Purchase Agreement
shall be determined in accordance with the laws of the State of Delaware,
without application of the conflict of laws principles thereof.

         (g) Severability. If any provision of the Plan or any Purchase
Agreement is or becomes or is deemed to be invalid, illegal, or unenforceable in
any jurisdiction or as to any Person or Purchase Agreement, or would disqualify
the Plan or any Purchase Agreement under any law deemed applicable by the
Committee, such provision shall be construed or deemed amended to conform to the
applicable laws, or if it cannot be construed or deemed amended without, in



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the determination of the Committee, materially altering the intent of the Plan
or the Purchase Agreement, such provision shall be stricken as to such
jurisdiction, Person or Purchase Agreement and the remainder of the Plan and any
such Purchase Agreement shall remain in full force and effect.

         (h) Other Laws. The Committee may refuse to issue or transfer any
Shares or other consideration under a Purchase Agreement if, acting in its sole
discretion, it determines that the issuance or transfer of such Shares or such
other consideration might violate any applicable law or regulation or entitle
the Company to recover the same under Section 16(b) of the Exchange Act, and any
payment tendered to the Company by a Participant in connection therewith shall
be promptly refunded to the relevant Participant. Without limiting the
generality of the foregoing, no Purchase Agreement shall be construed as an
offer to sell securities of the Company, and no such offer shall be outstanding,
unless and until the Committee in its sole discretion has determined that any
such offer, if made, would be in compliance with all applicable requirements of
the U.S. Federal securities laws and any other laws to which such offer, if
made, would be subject.

         (i) No Trust or Fund Created. Neither the Plan nor any Purchase
Agreement shall create or be construed to create a trust or separate fund of any
kind or a fiduciary relationship between the Company or any Affiliate and a
Participant or any other Person. To the extent that any Person acquires a right
to receive payments from the Company or any Affiliate pursuant to a Purchase
Agreement, such right shall be no greater than the right of any unsecured
general creditor of the Company or any Affiliate.

         (j) No Fractional Shares. No fractional Shares shall be issued or
delivered pursuant to the Plan or any Purchase Agreement, and the Committee
shall determine whether cash or other securities or other property shall be paid
or transferred in lieu of any fractional Shares or whether such fractional
Shares or any rights thereto shall be canceled, terminated, or otherwise
eliminated.

         SECTION 12. Effective Date. The Plan shall be effective as of May 22,
1998.



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