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                                                             Exhibit 10.34
                                                            [EXECUTION COPY]



                              FOURTH AMENDMENT TO
                       CREDIT AGREEMENT AND AMENDMENT TO
                        U.S. BORROWER SECURITY AGREEMENT

    THIS FOURTH AMENDMENT, dated as of August 23, 1996 (this "Amendment"), to
the Credit Agreement referred to below (and to the U.S. Borrower Security
Agreement referred to hereinbelow) is entered into among AAF-McQUAY INC.
(formerly known as SnyderGeneral Corporation), a Delaware corporation (the
"U.S. Borrower"), the Lenders parties hereto, THE BANK OF NOVA SCOTIA
("Scotiabank") and BANK BUMIPUTRA MALAYSIA BERHAD, NEW YORK BRANCH as the
managing agents (collectively referred to as the "Managing Agents") for the
Lenders, and Scotiabank as the administrative agent (the "Administrative
Agent") for the Lenders.

                              W I T N E S S E T H:

    WHEREAS, the U.S. Borrower, the Lenders and the Agents have heretofore
entered into the Credit Agreement, dated as of July 21, 1994 (together with
all Exhibits, Schedules and attachments thereto, in each case as amended or
otherwise modified prior to the date hereof, the "Credit Agreement");

    WHEREAS, in connection with the Credit Agreement the U.S. Borrower was
required to execute and deliver that certain U.S. Borrower Security Agreement,
dated as of July 21, 1994 (as amended or otherwise modified prior to the date
hereof, the "U.S. Borrower Security Agreement");

    WHEREAS, the U.S. Borrower has requested the Lenders and the Agents to
amend the Credit Agreement and the U.S. Borrower Security Agreement in certain
respects as set forth below; and

    WHEREAS, the Lenders and the Agents are willing, on and subject to the
terms and conditions set forth below, to amend the Credit Agreement in certain
respects as provided below (the Credit Agreement, as amended pursuant to the
terms of this Amendment, being referred to as the "Amended Credit Agreement")
and amend the U.S. Borrower Security Agreement as provided in Subpart 2.4
below;

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    NOW, THEREFORE, in consideration of the premises and the mutual
agreements herein contained, the U.S. Borrower, the Lenders and the Agents
hereby agree as follows:

PART I

                                  DEFINITIONS

    SUBPART 1.1.  Certain Definitions.  The following terms (whether or not
underscored) when used in this Amendment shall have the following meanings
(such meanings to be equally applicable to the singular and plural forms
thereof):

    "Administrative Agent" is defined in the preamble.

    "Amended Credit Agreement" is defined in the fourth recital.

    "Amendment" is defined in the preamble.

    "Amendment No. 4" is defined in Subpart 3.1.

    "Credit Agreement" is defined in the first recital.

    "Fourth Amendment Effective Date" is defined in Subpart 3.1.

    "Managing Agents" is defined in the preamble.

    "Scotiabank" is defined in preamble.
    
    "U.S. Borrower" is defined in the preamble.

    "U.S. Borrower Security Agreement" is defined in the second recital.

    SUBPART 1.2.  Other Definitions.  Terms for which meanings are provided
in the Credit Agreement are, unless otherwise defined herein or the context
otherwise requires, used in this Amendment with such meanings.

                                    PART II

                               AMENDMENTS TO THE
                                CREDIT AGREEMENT


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    Effective on (and subject to the occurrence of) the Fourth Amendment
Effective Date, the Credit Agreement is hereby amended in accordance with this
Part II and the U.S. Borrower Security Agreement is hereby amended in
accordance with Subpart 2.4; except as so amended or modified by this
Amendment, the Credit Agreement and the U.S. Borrower Security Agreement shall
continue in full force and effect.

    SUBPART 2.1.  Amendments to Article I.  Article I of the Credit Agreement
is hereby amended in accordance with Subparts 2.1.1 and 2.1.2.

    SUBPART 2.1.1.  Section 1.1 ("Defined Terms") of the Credit Agreement is
hereby amended by inserting in such Section the following definitions in the
appropriate alphabetical order:

         "Fourth Amendment" means the Fourth Amendment to Credit Agreement
    and Amendment to U.S. Borrower Security Agreement, dated as of August 23,
    1996, among the U.S. Borrower, the Lenders parties thereto and the
    Agents.

         "Fourth Amendment Effective Date" is defined in Subpart 3.1 of the
    Fourth Amendment.

    SUBPART 2.1.2.  Section 1.1 of the Credit Agreement is hereby further
amended as follows:

    (a) The definition of "Applicable Base Rate Margin" is hereby amended in
its entirety to read as follows:

         "Applicable Base Rate Margin" means, with respect to any Revolving
    Loan, Swing Line Loan or Term-A Loan made or maintained as a Base Rate
    Loan on or after the Fourth Amendment Effective Date, a per annum rate of
    interest determined by reference to the Leverage Ratio and Interest
    Coverage Ratio, in each case as indicated in the Compliance Certificate
    most recently delivered pursuant to clause (c) of Section 7.1.1, equal
    to:

              (a)  0% if the Leverage Ratio is less than 3.0:1 and the
         Interest Coverage Ratio is greater than 4.0:1;

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              (b)  .25% if the Leverage Ratio is less than 3.5:1 and the
         Interest Coverage Ratio is greater than 3.5:1 and the foregoing
         clause (a) does not apply;

              (c)  .375% if the Leverage Ratio is less than 3.75:1 and the
         Interest Coverage Ratio is greater than 3.25:1 and the foregoing
         clauses (a) and (b) do not apply;

              (d)  .50% if the Leverage Ratio is less than 4.0:1 and the
         Interest Coverage Ratio is greater than 3.0:1 and the foregoing
         clauses (a), (b) and (c) do not apply;

              (e)  .625% if the Leverage Ratio is less than 4.25:1 and the
         Interest Coverage Ratio is greater than 2.75:1 and the foregoing
         clauses (a), (b), (c) and (d) do not apply; and

              (f)  .875% if the Leverage Ratio is greater than or equal to
         4.25:1 or the Interest Coverage Ratio is less than or equal to
         2.75:1;

    provided, that, the Applicable Base Rate Margin shall only be decreased
    from the then existing Applicable Base Rate Margin if each of the
    Interest Coverage Ratio and Leverage Ratio (as reflected in the most
    recently delivered Compliance Certificate) is contained within the ranges
    set forth in the same clause (a), (b), (c), (d) or (e) above; provided,
    further, that, in the event the U.S. Borrower fails to deliver a
    Compliance Certificate within 45 days after the end of any Fiscal Quarter
    as required pursuant to clause (c) of Section 7.1.1, the Applicable Base
    Rate Margin from and including the 46th day after the end of such Fiscal
    Quarter to but not including the date the U.S. Borrower delivers to the
    Administrative Agent a Compliance Certificate shall conclusively be equal
    to .875%.

    (b) The definition of "Applicable L/C Rate Margin" is hereby amended in
its entirety to read as follows:

         "Applicable L/C Rate Margin" means, with respect to any Letter of
    Credit, on or at any time after the Fourth Amendment Effective Date, a
    per annum rate determined by 

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<PAGE>

    reference to the Leverage Ratio and Interest Coverage Ratio, in each case
    as indicated in the Compliance Certificate most recently delivered
    pursuant to clause (c) of Section 7.1.1, equal to:

              (a)  1.0% if the Leverage Ratio is less than 3.0:1 and the
         Interest Coverage Ratio is greater than 4.0:1;

              (b)  1.25% if the Leverage Ratio is less than 3.5:1 and the
         Interest Coverage Ratio is greater than 3.5:1 and the foregoing
         clause (a) does not apply;

              (c)  1.375% if the Leverage Ratio is less than 3.75:1 and the
         Interest Coverage Ratio is greater than 3.25:1 and the foregoing
         clauses (a) and (b) do not apply;

              (d)  1.50% if the Leverage Ratio is less than 4.0:1 and the
         Interest Coverage Ratio is greater than 3.0:1 and the foregoing
         clauses (a), (b)  and (c) do not apply;

              (e)  1.625% if the Leverage Ratio is less than 4.25:1 and the
         Interest Coverage Ratio is greater than 2.75:1 and the foregoing
         clauses (a), (b), (c) and (d) do not apply;

              (f)  1.875% if the Leverage Ratio is greater than or equal to
         4.25:1 or the Interest Coverage Ratio is less than or equal to
         2.75:1;

    provided, that, the Applicable L/C Rate Margin shall only be decreased
    from the then existing Applicable L/C Rate Margin if each of the Interest
    Coverage Ratio and Leverage Ratio (as reflected in the most recently
    delivered Compliance Certificate) is contained within the ranges set
    forth in the same clause (a), (b), (c), (d) or (e) above; provided,
    further, that, in the event the U.S. Borrower fails to deliver a
    Compliance Certificate within 45 days after the end of any Fiscal Quarter
    as required pursuant to clause (c) of Section 7.1.1, the Applicable L/C
    Rate Margin from and including the 46th day after the end of such Fiscal
    quarter to but not including the date the U.S. Borrower delivers to 

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    the Administrative Agent a Compliance Certificate shall conclusively be
    equal to 1.875%.

    (c) The definition of "Applicable LIBO Rate Margin" is hereby amended in
its entirety to read as follows:

         "Applicable LIBO Rate Margin" means, with respect to any Revolving
    Loan, Swing Line Loan or Term-A Loan made or maintained as a LIBO Rate
    Loan on or after the Fourth Amendment Effective Date, a per annum rate of
    interest determined by reference to the Leverage Ratio and Interest
    Coverage Ratio, in each case as indicated in the Compliance Certificate
    most recently delivered pursuant to clause (c) of Section 7.1.1, equal
    to:

              (a)  1.0% if the Leverage Ratio is less than 3.0:1 and the
         Interest Coverage Ratio is greater than 4.0:1;

              (b)  1.25% if the Leverage Ratio is less than 3.5:1 and the
         Interest Coverage Ratio is greater than 3.5:1 and the foregoing
         clause (a) does not apply;

              (c)  1.375% if the Leverage Ratio is less than 3.75:1 and the
         Interest Coverage Ratio is greater than 3.25:1 and the foregoing
         clauses (a) and (b) do not apply;

              (d)  1.50% if the Leverage Ratio is less than 4.0:1 and the
         Interest Coverage Ratio is greater than 3.0:1 and the foregoing
         clauses (a) ,(b) and (c) do not apply;

              (e)  1.625% if the Leverage Ratio is less than 4.25:1 and the
         Interest Coverage Ratio is greater than 2.75:1 and the foregoing
         clauses (a), (b), (c) and (d) do not apply; and

              (f)  1.875% if the Leverage Ratio is greater than or equal to
         4.25:1 or the Interest Coverage Ratio is less than or equal to
         2.75:1;

    provided, that, (x) the Applicable LIBO Rate Margin shall not apply to
    Swing Line Loans and (y) the Applicable LIBO Rate Margin shall only be
    decreased from the then existing 

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    Applicable LIBO Rate Margin if each of the Interest Coverage Ratio and
    Leverage Ratio (as reflected in the most recently delivered Compliance
    Certificate) is contained within the ranges set forth in the same clause
    (a), (b), (c), (d) or (e) above; provided, further, that, in the event
    the U.S. Borrower fails to deliver a Compliance Certificate within
    45 days after the end of any Fiscal Quarter as required pursuant to
    clause (c) of Section 7.1.1, the Applicable LIBO Rate Margin from and
    including the 46th day after the end of such Fiscal Quarter to but not
    including the date the U.S. Borrower delivers to the Administrative Agent
    a Compliance Certificate shall conclusively be equal to 1.875%.

    (d) The definition of "Borrowing Base Amount" is hereby amended in its
entirety to read as follows:

         "Borrowing Base Amount" means, at any time on or after the Fourth
    Amendment Effective Date, the sum (without duplication) of

              (a)  the Net Asset Value of all Eligible Accounts of the U.S.
         Borrower at such time as certified by the U.S. Borrower to the
         Lenders in the most recently delivered Borrowing Base Certificate,

    plus

              (b)  the Net Asset Value of all Eligible Inventory of the U.S.
         Borrower at such time as certified by the U.S. Borrower to the
         Lenders in the most recently delivered Borrowing Base Certificate.

    (e) The definition of "Commitment Fee Rate" is hereby amended in its
entirety to read as follows:

         "Commitment Fee Rate" means, on or at any time after the Fourth
    Amendment Effective Date, a per annum rate determined by reference to the
    Leverage Ratio and Interest Coverage Ratio, in each case as indicated in
    the Compliance Certificate most recently delivered pursuant to clause (c)
    of Section 7.1.1, equal to:

              (a)  .25% if the Leverage Ratio is less than 3.0:1 and the
         Interest Coverage Ratio is greater than 4.0:1;

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<PAGE>

              (b)  .30% if the Leverage Ratio is less than 3.5:1 and the
         Interest Coverage Ratio is greater than 3.5:1 and the foregoing
         clause (a) does not apply;

              (c)  .325% if the Leverage Ratio is less than 3.75:1 and the
         Interest Coverage Ratio is greater than 3:25:1 and the foregoing
         clauses (a) and (b) do not apply;

              (d)  .375% if the Leverage Ratio is less than 4.0:1 and the
         Interest Coverage Ratio is greater than 3.0:1 and the foregoing
         clauses (a), (b) and (c) do not apply;

              (e)  .375% if the Leverage Ratio is less than 4.25:1 and the
         Interest Coverage Ratio is greater than 2.75:1 and the foregoing
         clauses (a), (b), (c) and (d) do not apply; and

              (f)  .50% if the Leverage Ratio is greater than or equal to
         4.25:1 or the Interest Coverage Ratio is less than or equal to
         2.75:1;

    provided, that, the Commitment Fee Rate shall only be decreased from the
    then existing Commitment Fee Rate if each of the Interest Coverage Ratio
    and Leverage Ratio (as reflected in the most recently delivered
    Compliance Certificate) is contained within the ranges set forth in the
    same clause (a), (b), (c), (d) or (e) above; provided, further, that, in
    the event the U.S. Borrower fails to deliver a Compliance Certificate
    within 45 days after the end of any Fiscal Quarter as required pursuant
    to clause (c) of Section 7.1.1, the Commitment Fee Rate from and
    including the 46th day after the end of such Fiscal Quarter to but not
    including the date the U.S. Borrower delivers to the Administrative Agent
    a Compliance Certificate shall conclusively be equal to .50%.

    (f) The definition of "Disqualified Account" is hereby amended in its
entirety to read as follows:

         "Disqualified Account" of any Person means an Account which, when
    scheduled to the Administrative Agent or at any time thereafter, is of
    any of the following types:

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              (a)  such Account (i) is unpaid more than seventy-five (75)
         days after the due date stated on the original invoice or (ii) has a
         stated due date more than thirty (30) days after the date of such
         original invoice and is unpaid more than one hundred and thirty-five
         (135) days after the date of such original invoice;

              (b)  such Account arises out of a sale not made in the ordinary
         course of such Person's business, or a sale to a Person which is an
         Affiliate of the U.S. Borrower, or controlled by an Affiliate or
         employee of the U.S. Borrower;

              (c)  such Account fails to meet or violates any warranty,
         representation or covenant contained in this Agreement or any of the
         other Loan Documents relating to the Accounts of such Person;

              (d)  such Account is owing from an account debtor

                   (i)  which has filed a petition for bankruptcy or any
              other petition for relief under the Bankruptcy Code or any
              similar statute (unless the account debtor is a
              debtor-in-possession in a Chapter 11 case and has available
              debtor-in-possession financing from sources and under terms
              reasonably acceptable to the Administrative Agent and the
              Account is entitled to priority under Section 507 of the
              Bankruptcy Code as an administrative expense allowed under
              Section 503(b) of the Bankruptcy Code), or made an assignment
              for the benefit of creditors,

                   (ii)  against which any petition or other application for
              relief under the Bankruptcy Code or any similar statute has
              been filed or

                   (iii)  which has failed, suspended its business
              operations, become insolvent, suffered a receiver or a trustee
              to be appointed for any of its assets or affairs, or is
              generally failing to pay its debts as they become due;

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<PAGE>

              (e)  such Account arises from a sale to an account debtor
         outside the United States or Canada, unless the account debtor's
         obligations (or that portion of such obligations which is acceptable
         to the Administrative Agent) with respect to such sale are secured
         by a letter of credit, guaranty or eligible bankers' acceptance
         having terms, and from such issuers and confirmation banks, as are
         acceptable to the Administrative Agent;

              (f)  such Account is owing from an account debtor if fifty
         percent (50%) or more of all Accounts owing from such account debtor
         are past due pursuant to the criteria set forth in clause (a) of
         this definition;

              (g)  such Account is one in which the Administrative Agent does
         not have a senior, perfected security interest in, or such Account
         is subject to a Lien which is not permitted under Section 7.2.3; or

              (h)  such Account arises from a sale made to an account debtor
         on cash terms.

    (g) The definition of "Letter of Credit Commitment Amount" is hereby
amended in its entirety to read as follows:

         "Letter of Credit Commitment Amount" means, on any date on or after
    the Fourth Amendment Effective Date, a maximum Dollar Equivalent of
    $75,000,000, as such amount may be permanently reduced from time to time
    pursuant to Section 2.2.

    (h) The definition of "Net Asset Value" is hereby amended in its entirety
to read as follows:

         "Net Asset Value" means, at any time of any determination thereof,
    for any time on or after the Fourth Amendment Effective Date,

              (a)  an amount equal to 85% of the book value of all Eligible
         Accounts as reflected on the books of the U.S. Borrower and the
         applicable U.S. Subsidiaries, in accordance with GAAP, net of all
         credits, discounts and 

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         allowances that have not already been deducted pursuant to the
         definition of "Disqualified Accounts"; and

              (b)  an amount (without duplication) equal to (i) 60% of all
         Eligible Inventory consisting of finished goods and raw material and
         (ii) 20% of all Eligible Inventory consisting of work-in-process, in
         each case based on the lesser of the market value and the cost of
         goods (determined on a first-in, first-out basis) and as reflected
         on the books of the U.S. Borrower and the applicable U.S.
         Subsidiaries, in each case as at such time, based on the lesser of
         the market value and the cost of goods in accordance with GAAP and
         net of related book reserves that have not already been deducted
         pursuant to the definition of "Disqualified Inventory".

    (i) The definition of "Revolving Loan Commitment Amount" is hereby
amended in its entirety to read as follows:

         "Revolving Loan Commitment Amount" means, at any time on or after
    the Fourth Amendment Effective Date, $100,000,000, as such amount may be
    reduced from time to time pursuant to Section 2.2.

    (j) Clause (b) of the definition of "Revolving Loan Commitment
Termination Date" is hereby amended in its entirety to read as follows:

         (b)  February 14, 2001, the fifth-year anniversary of the Third
    Amendment Effective Date;

    (k) The definition of "Stated Maturity Date" is hereby amended in its
entirety to read as follows:

         "Stated Maturity Date" means February 14, 2001, the fifth-year
    anniversary of the Third Amendment Effective Date.

    (l) The definition of "Third Amendment Effective Date" is hereby amended
in its entirety to read as follows:

         "Third Amendment Effective Date" means February 14, 1996.

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    SUBPART 2.2.  Amendments to Article VII.  Article VII of the Credit
Agreement is hereby amended in accordance with Subparts 2.2.1 through 2.2.8.

    SUBPART 2.2.1.  Section 7.1.6 ("Future Subsidiaries") of the Credit
Agreement is hereby amended by inserting immediately following the clause
which reads "or a directly-owned Foreign Subsidiary of the U.S. Borrower or a
U.S. Subsidiary of the U.S. Borrower" appearing in the first sentence of such
Section a new clause which shall read as follows: "with total assets which, in
the aggregate, equal or exceed $500,000 as of, initially, the time such Person
becomes such a Foreign Subsidiary and, at any time thereafter, as of the end
of any succeeding Fiscal Quarter".

    SUBPART 2.2.2.  Clause (c) of Section 7.2.2 ("Indebtedness") of the
Credit Agreement is hereby amended in its entirety to read as follows:

         (c)  Indebtedness

              (i)  existing as of the Effective Date which is identified in
         Item 7.2.2(c) ("Ongoing Indebtedness") of the Disclosure Schedule
         and any extensions, renewals, refundings or replacements thereof;
         provided, that any such extension, renewal, refunding or replacement
         is in an aggregate principal amount not greater than the principal
         amount of, and is on terms no less favorable to the obligor thereof
         than the terms of, the Indebtedness so extended, renewed, refunded
         or replaced; and

              (ii)  in respect of the Senior Notes in an aggregate principal
         amount not to exceed $125,000,000, and interest thereon;

    SUBPART 2.2.3.  Clause (c) of Section 7.2.3 ("Liens") of the Credit
Agreement is hereby amended in its entirety to read as follows:

         (c)  Liens identified in Item 7.2.3(c) ("Ongoing Liens") of the
    Disclosure Schedule and granted prior to the Effective Date to secure the
    payment of Indebtedness of the type permitted and described in
    clause (c)(i) of Section 7.2.2;

                                      -12-
<PAGE>

    SUBPART 2.2.4.  Clause (j) of Section 7.2.5 ("Investments") of the Credit
Agreement is hereby amended in its entirety to read as follows:

         (j)  Investments by the U.S. Borrower in (i) the U.K. Subsidiary
    and/or the Guernsey Subsidiary in an aggregate amount not to exceed
    $30,000,000 and (ii) until September 30, 1996, the Receivables Entity in
    an aggregate amount not to exceed $6,000,000;

    SUBPART 2.2.5.  The last sentence of Section 7.2.5 ("Investments") of the
Credit Agreement is hereby amended in its entirety to read as follows:

    Notwithstanding the foregoing, neither the U.S. Borrower nor any
    Subsidiary of the U.S. Borrower shall make any Investment in any
    Restricted Subsidiary so long as such Subsidiary is a Restricted
    Subsidiary; provided, that if a Subsidiary of the U.S. Borrower becomes a
    "Restricted Subsidiary" pursuant to clause (c) of the definition thereof,
    then Investments in such Restricted Subsidiary which were made or
    permitted under this Section 7.2.5 prior to such Subsidiary becoming a
    Restricted Subsidiary shall continue to be permitted under this Section
    and such Investments shall not constitute an Event of Default.

    SUBPART 2.2.6.  Section 7.2.7 ("Capital Expenditures, etc.") of the
Credit Agreement is hereby amended by deleting the amount "$19,000,000" set
forth opposite the Fiscal Year "1997" appearing in the first sentence of such
Section and inserting in lieu thereof the amount "$21,000,000".

    SUBPART 2.2.7.  Section 7.2.11 ("Asset Dispositions, etc.") of the Credit
Agreement is hereby amended by (i) inserting the word "or" at the end of
clause (d) of such Section, (ii) deleting clause (f) in its entirety and (iii)
deleting the semicolon (";") and the word "or" at the end of clause (e) of
such Section and inserting a period (".") in lieu thereof.

    SUBPART 2.2.8.  Section 7.2.12 ("Modification of Certain Agreements") of
the Credit Agreement is hereby amended in its entirety to read as follows:

                                      -13-
<PAGE>

         SECTION 7.2.12.  Modification of Certain Agreements.  The U.S.
    Borrower will not, without the prior consent of the Agents, consent to
    any amendment, supplement or other modification of any of the terms or
    provisions contained in, or applicable to, the Stock Purchase Agreement,
    the Seller Note, the Tax Indemnification Agreement, the Senior Note
    Indenture, the Senior Notes or any document or instrument evidencing or
    applicable to any Subordinated Debt, other than any amendment, supplement
    or other modification which extends the date or reduces the amount of any
    required repayment or redemption.

    SUBPART 2.3.  Amendment to Article VIII.  Section 8.1.5 ("Default on
other Indebtedness") of the Credit Agreement is hereby amended in its entirety
to read as follows:

         SECTION 8.1.5.  Default on Other Indebtedness.  (a)  An "Event of
    Default" (as defined in the Senior Note Indenture) shall have occurred
    and be continuing under the Senior Note Indenture or (b) a default shall
    occur in the payment when due (subject to any applicable grace period),
    whether by acceleration or otherwise, of any Indebtedness (other than
    Indebtedness described in Section 8.1.1) of the U.S. Borrower or any of
    its Subsidiaries or any other Obligor having a principal amount,
    individually or in the aggregate, in excess of $1,000,000, or a default
    shall occur in the performance or observance of any obligation or
    condition with respect to such Indebtedness if the effect of such default
    is to accelerate the maturity of any such Indebtedness or such default
    shall continue unremedied for any applicable period of time sufficient to
    permit the holder or holders of such Indebtedness, or any trustee or
    agent for such holders, to cause such Indebtedness to become due and
    payable prior to its expressed maturity.

    SUBPART 2.4.  Amendment to the U.S. Borrower Security Agreement.  Clause
(c) of Section 2.1 of the U.S. Borrower Security Agreement is hereby amended
in its entirety to read as follows:

         (c)  all accounts, contracts, contract rights, chattel paper,
    documents, instruments, and general intangibles of the Grantor, whether
    or not arising out of or in connection with the sale or lease of goods or
    the rendering of 

                                      -14-
<PAGE>

    services, and all rights of the Grantor now or hereafter existing in and
    to all security agreements, guaranties, leases and other contracts
    securing or otherwise relating to any such accounts, contracts, contract
    rights, chattel paper, documents, instruments, and general intangibles
    (any and all such accounts, contracts, contract rights, chattel paper,
    documents, instruments, and general intangibles being the "Receivables",
    and any and all such security agreements, guaranties, leases and other
    contracts being the "Related Contracts");

    SUBPART 2.5.  Conforming Amendments to Exhibit F to Credit Agreement. 
Exhibit F (Form of Borrowing Base Certificate) to the Credit Agreement is
hereby amended in its entirety to read as set forth in Annex III hereto.

    SUBPART 2.6.  Covenant Compliance and Rates and Fees in respect of Loans
and Letters of Credit outstanding or issued prior to the Fourth Amendment
Effective Date.  Notwithstanding anything in the foregoing to the contrary,
any determination of applicable interest rates and fees in respect of Loans
and Letters of Credit outstanding or issued under the Credit Agreement prior
to the Fourth Amendment Effective Date, and any determination of compliance
with the provisions of the Credit Agreement (including with the financial
covenants set forth in Section 7.2.4 of the Credit Agreement) for any period
prior to the Fourth Amendment Effective Date, shall be made pursuant to the
terms of the Credit Agreement as in effect immediately prior to the Fourth
Amendment Effective Date and the defined terms applicable to any such
determination shall have the meanings provided in the Credit Agreement as in
effect immediately prior to the Fourth Amendment Effective Date.


                                    PART III

                    CONDITIONS TO EFFECTIVENESS; EXPIRATION

    SUBPART 3.1.  Fourth Amendment Effective Date.  This Amendment, and the
amendments and modifications contained herein, shall be and become effective
on the date (the "Fourth Amendment Effective Date") when each of the
conditions set forth in this Subpart 3.1 shall have been fulfilled to the
satisfaction of the Administrative Agent and each of the Lenders; provided,
that, 

                                      -15-
<PAGE>

such date shall occur prior to the termination date set forth in Subpart 3.2
(whereupon this Amendment shall be known and may be referred to as "Amendment
No. 4").

    SUBPART 3.1.1.  Execution of Counterparts.  The Administrative Agent
shall have received counterparts of this Amendment, duly executed and
delivered on behalf of the U.S. Borrower, each Agent and each of the Lenders.

    SUBPART 3.1.2.  Affirmation and Consent. (a)  The Administrative Agent
shall have received, with counterparts for each Lender, a duly executed copy
of the Obligor Affirmation and Consent to this Amendment, substantially in the
form of Annex I hereto and duly executed and delivered by each of the Obligors
parties thereto.

    (b) The Administrative Agent shall have received, with counterparts for
each Lender, a duly executed copy of the  Shareholder Affirmation and Consent
to this Amendment, substantially in the form of Annex II hereto and duly
executed and delivered by each of the Initial Shareholders parties thereto.

    SUBPART 3.1.3.  Resolutions, etc.  The Administrative Agent shall have
received from each of the U.S. Borrower and each other Obligor a certificate,
dated the Fourth Amendment Effective Date, of its Secretary or Assistant
Secretary as to

         (a) resolutions of its Board of Directors then in full force and
    effect authorizing the execution, delivery and performance of this
    Amendment and each other Loan Document to be executed by it; and

         (b) the incumbency and signatures of those of its officers
    authorized to act with respect to this Amendment, and each other Loan
    Document to be executed by it,

upon which certificate each Lender may conclusively rely until it shall have
received a further certificate of the Secretary or Assistant Secretary of such
Obligor cancelling or amending such prior certificate.

    SUBPART 3.1.4.  Termination of the Receivables Purchase Facility, Payment
of all Obligations thereunder and Release of 

                                      -16-
<PAGE>

Liens.  The Administrative Agent shall have received evidence satisfactory to
it that the Receivables Purchase Agreement and each of the other Receivables
Purchase Facility Documents have been terminated by the parties thereto and
are of no further force or effect, all commitments (if any) thereunder or in
connection therewith have been terminated, all fees, costs, and amounts
(whether in respect of principal, interest, fees or premium) payable under or
in connection with the Receivables Purchase Facility Documents have been paid
in full, and all Liens securing payment of any such fees, costs or amounts
have been released and the Administrative Agent shall have received all
Uniform Commercial Code Form UCC-3 termination statements or other instruments
as may be suitable or appropriate in connection therewith.  In furtherance of
(but not in limitation of) the foregoing, the Administrative Agent shall have
received (a) a statement as to the aggregate amount owing under the
Receivables Purchase Facility Documents, (b) copies of documents satisfactory
to the Administrative Agent, executed on behalf of the requisite parties
reconveying the receivables sold under the Receivables Purchase Facility
Documents to the Receivables Entity and releasing all right, title and
interests in such receivables together with executed releases of all financing
statements filed with respect thereto (the "Subject Documents"), (c) a letter
from the Receivables Agent under the Receivables Purchase Facility Documents
to the effect that upon payment of the outstanding balance under the
Receivables Purchase Facility Documents, the Subject Documents will be
released to the Administrative Agent and may be recorded, (d) executed
documents of transfer satisfactory to the Administrative Agent conveying all
receivables from the Receivables Entity to the U.S. Borrower free and clear of
all Liens, together with executed releases of all financing statements filed
by the Receivables Entity with respect to such receivables, and (e) evidence
acceptable to the Administrative Agent that all commitments (if any) under the
Receivables Purchase Facility Documents will be terminated upon payment of the
outstanding balance under the Receivables Purchase Facility Documents.

    SUBPART 3.1.5.  Material Adverse Change.  Since June 30, 1995, there
shall have been no material adverse change in the financial condition,
operations, assets, business, properties or prospects of the U.S. Borrower or
the U.S. Borrower and its Subsidiaries, taken as a whole.

                                      -17-
<PAGE>

    SUBPART 3.1.6.  Amendments to Mortgages.  The Administrative Agent shall
have received counterparts of all amendments to Mortgages previously delivered
pursuant to Section 5.1.14 of the Credit Agreement (as such Mortgages may have
been amended or otherwise modified prior to the Fourth Amendment Effective
Date), dated as of (or a date reasonably near to) the Fourth Amendment
Effective Date, duly executed by the appropriate Obligor, each such amendment
(together in each case with an endorsement to the applicable title insurance
policy) in form and substance satisfactory to the Administrative Agent, as the
Administrative Agent may require.

    SUBPART 3.1.7.  Opinions of Counsel.  The Administrative Agent shall have
received such opinions, each dated the Fourth Amendment Effective Date, in
form and substance and from counsel satisfactory to, and as may be required
by, the Administrative Agent and each of the Lenders.

    SUBPART 3.1.8.  Closing Fees, Expenses, etc.  The Administrative Agent
shall have received for its own account, or for the account of each Agent and
each Lender, as the case may be, all fees, costs and expenses due and payable
as of the Fourth Amendment Effective Date (including pursuant to Sections 3.3
and 10.3 of the Credit Agreement).

    SUBPART 3.1.9.  Legal Details, etc.   All documents executed or submitted
pursuant hereto shall be satisfactory in form and substance to the
Administrative Agent and its counsel.  The Administrative Agent and its
counsel shall have received all information and such counterpart originals or
such certified or other copies or such materials as the Administrative Agent
or its counsel may reasonably request, and all legal matters incident to the
transactions contemplated by this Amendment shall be satisfactory to the
Administrative Agent and its counsel.

    SUBPART 3.2.  Expiration.  If the Fourth Amendment Effective Date shall
not have occurred on or prior to September 2, 1996, the agreements of the
parties hereto contained in this Amendment shall terminate effective
immediately on such date and without any further action.

                                      -18-
<PAGE>

                                    PART IV

                        MISCELLANEOUS; REPRESENTATIONS;
                          GRANT OF ADDITIONAL SECURITY

    SUBPART 4.1.  Cross-References.  References in this Amendment to any Part
or Subpart are, unless otherwise specified or otherwise required by the
context, to such Part or Subpart of this Amendment.

    SUBPART 4.2.  Loan Document Pursuant to Credit Agreement.  This Amendment
is a Loan Document executed pursuant to the Credit Agreement and shall be
construed, administered and applied in accordance with all of the terms and
provisions of the Credit Agreement (and, following the Fourth Amendment
Effective Date, the Amended Credit Agreement).

    SUBPART 4.3.  Full Force and Effect; Limited Amendment. Except as
expressly amended hereby, all of the representations, warranties, terms,
covenants, conditions and other provisions of the Credit Agreement and the
other Loan Documents shall remain unamended and unwaived and shall continue to
be, and shall remain, in full force and effect in accordance with their
respective terms.  The amendments set forth herein shall be limited precisely
as provided for herein to the provisions expressly amended herein and shall
not be deemed to be an amendment to, waiver of, consent to or modification of
any other term or provision of the Credit Agreement, any other Loan Document
referred to therein or herein or of any transaction or further or future
action on the part of the U.S. Borrower or any other Obligor which would
require the consent of the Lenders under the Credit Agreement or any of the
other Loan Documents.

    SUBPART 4.4.  Payment of Fees and Expenses.  The U.S. Borrower hereby
agrees to pay and reimburse the Administrative Agent for all of its reasonable
fees and expenses incurred in connection with the negotiation, preparation,
execution and delivery of this Amendment and related documents, including all
reasonable fees and disbursements of counsel to the Administrative Agent.

    SUBPART 4.5.  Successors and Assigns.  This Amendment shall be binding
upon and inure to the benefit of the parties hereto and their respective
successors and assigns.

                                      -19-
<PAGE>

    SUBPART 4.6.  Counterparts.  This Amendment may be executed by the
parties hereto in several counterparts, each of which when executed and
delivered shall be deemed to be an original and all of which shall constitute
together but one and the same agreement.

    SUBPART 4.7.  Governing Law.  THIS AMENDMENT SHALL BE GOVERNED BY AND
CONSTRUED IN ACCORDANCE WITH THE INTERNAL LAWS OF THE STATE OF NEW YORK.

    SUBPART 4.8.  Compliance with Warranties, No Default, etc.  Both before
and after giving effect to the occurrence of the Fourth Amendment Effective
Date and the amendments to the Credit Agreement set forth above, the U.S.
Borrower represents and warrants to the Agents and the Lenders that the
following statements are true and correct:

         (a)  the representations and warranties set forth in Article VI
    (excluding, however, those contained in Section 6.7 and clause (c) of
    Section 6.11) of the Credit Agreement and in each other Loan Document
    (including the U.S. Borrower Security Agreement) are true and correct in
    all material respects with the same effect as if then made (unless stated
    to relate solely to an earlier date, in which case such representations
    and warranties were true and correct as of such earlier date);

         (b)  except as disclosed by the U.S. Borrower to the Administrative
    Agent and the Lenders pursuant to Section 6.7 of the Credit Agreement and
    clause (c) of Section 6.11 of the Credit Agreement,

              (i)  no labor controversy, litigation, arbitration or
         governmental investigation or proceeding shall be pending or, to the
         knowledge of the U.S. Borrower, threatened against the U.S. Borrower
         or any of its Subsidiaries which is reasonably likely to materially
         adversely affect the U.S. Borrower's consolidated business,
         operations, assets, revenues, properties or prospects or which
         purports to affect the legality, validity or enforceability of this
         Amendment, the Amended Credit Agreement or any other Loan Document;
         and

                                      -20-
<PAGE>

              (ii)  no development has occurred in any labor controversy,
         litigation, arbitration or governmental investigation or proceeding
         disclosed pursuant to Section 6.7 of the Credit Agreement or
         clause (c) of Section 6.11 of the Credit Agreement which is
         reasonably likely to materially adversely affect the consolidated
         businesses, operations, assets, revenues, properties or prospects of
         the U.S. Borrower and its Subsidiaries; and

         (c)  no Default shall have then occurred and be continuing.

    SUBPART 4.9.  Additional General Representations.  In order to induce the
Lenders and the Agents to enter into this Amendment, the U.S. Borrower hereby
additionally represents and warrants as follows:

         (a) the execution and delivery of this Amendment and the performance
    by the U.S. Borrower, each of its Subsidiaries (including AAFH) and each
    other Obligor of each of their respective obligations hereunder, under
    each other Loan Document, under the Credit Agreement as amended hereby
    and, upon the occurrence of the Fourth Amendment Effective Date, under
    the Amended Credit Agreement are within such Person's corporate powers,
    have been duly authorized by all necessary corporate action, have
    received all necessary governmental approval (if any shall be required),
    and do not (i) contravene such Person's Organic Documents,
    (ii) contravene any contractual restriction, law or governmental
    regulation or court decree or order binding on or affecting such Person
    or (iii) result in, or require the creation or imposition of, any Lien on
    any of such Person's properties (other than pursuant to a Loan Document);
    and

         (b)  this Amendment, each other Loan Document, the Credit Agreement
    as amended hereby and, upon the occurrence of the Fourth Amendment
    Effective Date, the Amended Credit Agreement are the legal, valid and
    binding obligations of the U.S. Borrower, each of its Subsidiaries
    (including AAFH) and each other Obligor enforceable in accordance with
    their respective terms (except as such enforceability may be limited by
    applicable bankruptcy, insolvency, reorganization 

                                      -21-
<PAGE>

    or similar laws affecting creditors' rights generally and by principles
    of equity).

    SUBPART 4.10.  Grant of Additional Security.  In order to induce the
Agents and the Lenders to enter into this Amendment and thereby, among other
things, increase the Revolving Loan Commitment Amount and the Letter of Credit
Commitment Amount and provide for the inclusion of "Eligible Accounts" in the
computation of the "Borrowing Base Amount", the U.S. Borrower hereby assigns
and pledges to the Administrative Agent for its benefit and the ratable
benefit of each of the Lenders and the Issuers, and hereby grants to the
Administrative Agent, for its benefit and the ratable benefit of each of the
Lenders and the Issuers, a security interest in all of the following, whether
now or hereafter existing or acquired, and in addition to (and in no way in
limitation of) any and all of the other "Collateral" under (and as such term
is defined in) the U.S. Borrower Security Agreement, all accounts, contracts,
contract rights, chattel paper, documents, instruments, and general
intangibles of the U.S. Borrower, whether or not arising out of or in
connection with the sale or lease of goods or the rendering of services, and
all rights of the U.S. Borrower now or hereafter existing in and to all
security agreements, guaranties, leases and other contracts securing or
otherwise relating to any such accounts, contracts, contract rights, chattel
paper, documents, instruments, and general intangibles.

    SUBPART 4.11.  Extension of Liens.  In addition to, and in no way in
limitation of, the forgoing Subpart 4.10, the U.S. Borrower hereby extends all
Liens currently securing the Obligations until the same have been fully paid,
and all such Liens are hereby ratified and confirmed.  The U.S. Borrower
hereby acknowledges that none of the Liens or other rights securing the
payment of the Obligations are released, diminished, or affected hereby, and
the same are recognized to be valid and subsisting.

    SUBPART 4.12.  Representations and Warranties as to Additional Security. 
In furtherance of the foregoing Subparts 4.10 and 4.11, the U.S. Borrower
hereby represents and warrants to the Agents and the Lenders that the
following statements are true:

                                      -22-
<PAGE>

         (a) the representations and warranties made by the U.S. Borrower as
    Grantor under the U.S. Borrower Security Agreement (including after
    giving effect to the amendment thereto pursuant to Subpart 2.4) are true
    and correct as of the date hereof;

         (b) the place(s) of business and chief executive office of the U.S.
    Borrower and the office(s) where the U.S. Borrower keeps its records
    concerning the Receivables are located at the address set forth below the
    name of the U.S. Borrower on the signature page hereof; and

         (c) the U.S. Borrower Security Agreement, together with the grant of
    the security interest pursuant to the foregoing Subpart 4.10 and the
    continuance of the UCC-1 Financing Statements filed in the jurisdictions
    set forth on Schedule I hereto (each of such financing statements is in
    appropriate form and has been duly filed in all appropriate filing
    offices), creates a valid and perfected first priority security interest
    in all "Collateral" under (and as such term is defined in) the
    U.S. Borrower Security Agreement (including after giving effect to the
    amendment thereto pursuant to Subpart 2.4) of the U.S. Borrower, securing
    the payment of the Obligations, and all filings and other actions
    necessary or reasonably desirable to perfect and protect such security
    interest have been duly taken.

    SUBPART 4.13.  Adjusted Percentages.  Each of the Lenders party hereto
hereby acknowledges and agrees that upon the occurrence of the Fourth
Amendment Effective Date, such Lender's Percentage for purposes of the Amended
Credit Agreement shall be as set forth opposite its signature hereto, as such
percentage may be amended from time to time hereafter, including pursuant to
Lender Assignment Agreement(s) executed by such Lender and its Assignee
Lender(s) and delivered pursuant to Section 10.11 of the Amended Credit
Agreement.

 
                                      -23-
<PAGE>

    IN WITNESS WHEREOF, the parties hereto have caused this Amendment to be
executed by their respective duly authorized officers as of the day and year
first above written.

                                            AAF-McQUAY INC. (formerly known
                                              as 
                                              SnyderGeneral Corporation)


                                            By /s/BARTON BAILEY
                                            Title: Vice President 



                                            THE BANK OF NOVA SCOTIA, as
                                              Administrative Agent and
                                              as a Managing Agent


                                            By /s/AUTHORIZED SIGNATURE
                                            Title:  Unit Head



                                            BANK BUMIPUTRA MALAYSIA BERHAD,
                                                 NEW
                                            YORK BRANCH, as a Managing Agent


                                            By /s/AUTHORIZED SIGNATURE
                                            Title:  


                                            LENDERS:

Revolving Loan Commitment:                  THE BANK OF NOVA SCOTIA
     30.58720932%

Term-A Loan Commitment:                     By /s/AUTHORIZED SIGNATURE
     16.20930230%                           Title:  Unit Head



Revolving Loan Commitment:                  BANK BUMIPUTRA MALAYSIA BERHAD,
                                            NEW

                                      -24-
<PAGE>

     15.66720930%                           YORK BRANCH

Term-A Loan Commitment:
     16.20930233%                           By /s/AUTHORIZED SIGNATURE
                                            Title:  



Revolving Loan Commitment:                  BANK OF AMERICA NATIONAL TRUST AND
     21.18744186%                           SAVINGS ASSOCIATION

Term-A Loan Commitment:
     13.44186047%                           By /s/AUTHORIZED SIGNATURE
                                            Title:  



Revolving Loan Commitment:                  CITICORP USA, INC.
      8.13953488%

Term-A Loan Commitment:                     By /s/AUTHORIZED SIGNATURE
      5.53488373%                           Title:        



Revolving Loan Commitment:                  THE LONG-TERM CREDIT BANK OF JAPAN,
      8.13953488%                           LIMITED NEW YORK BRANCH

Term-A Loan Commitment:
      5.53488373%                           By /s/JAY SHANKAR
                                            Title:  Vice President



Revolving Loan Commitment:                  SOCIETE GENERALE, SOUTHWEST AGENCY
      8.13953488%

Term-A Loan Commitment:                     By /s/AUTHORIZED SIGNATURE
      5.53488373%                           Title:  


                                      -25-
<PAGE>

Revolving Loan Commitment:                  COMERICA BANK
      8.13953488%

Term-A Loan Commitment:                     By /s/AUTHORIZED SIGNATURE
      5.53488373%                           Title


 

                                      -26-
<PAGE>

Revolving Loan Commitment:                  RESTRUCTURED OBLIGATIONS BACKED BY
      0.00000000%                           SENIOR ASSETS B.V.

Term-A Loan Commitment:                     By Chancellor Senior Secured
     12.00000000%                              Management, Inc., as
                                               Portfolio Advisor


                                            By /s/GREGORY L. SMITH 
                                            Title: Vice President



Revolving Loan Commitment:                  CRESCENT/MACH I PARTNERS, L.P.
      0.00000000%
                                            By TCW Asset Management Company,
Term-A Loan Commitment:                     its Investment Manager
      9.33333333%

                                            By /s/AUTHORIZED SIGNATURE
                                            Title:  



Revolving Loan Commitment:                  CERES FINANCE LTD.
      0.00000000%

Term-A Loan Commitment:                     By /s/AUTHORIZED SIGNATURE
      7.16000000%                           Title:  Director



Revolving Loan Commitment:                  STRATA FUNDING LTD.
      0.00000000%

Term-A Loan Commitment:                     By /s/AUTHORIZED SIGNATURE
      3.50666667%                           Title:  Director


                                      -27-