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                                                                   Exhibit 10.21

                    FOURTH AMENDMENT TO CREDIT AGREEMENT AND
                              FORBEARANCE AGREEMENT

       THIS FOURTH AMENDMENT TO CREDIT AGREEMENT AND FORBEARANCE AGREEMENT (this
"Agreement"), dated as of June 28, 2002, is entered into by and among ADVANCED
GLASSFIBER YARNS, LLC, a Delaware limited liability company ("Borrower"), the
subsidiaries of Borrower signatory hereto as guarantors ("Guarantors"), the
Required Lenders signatory hereto, and WACHOVIA BANK, NATIONAL ASSOCIATION
(f/k/a First Union National Bank, a national banking association), in its
capacity as Administrative Agent for the Lenders ("Agent").

                                    RECITALS:

       WHEREAS, Borrower, certain Domestic Subsidiaries (as defined therein) of
Borrower signatory thereto, the Lenders (as defined therein) signatory thereto,
and Agent are parties to that certain Credit Agreement dated as of September 30,
1998; as amended by that certain Syndication Amendment and Assignment dated as
of November 24, 1998, that certain Second Amendment to Credit Agreement dated as
of December 16, 1999, and that certain Third Amendment to Credit Agreement and
Waiver dated as of December 14, 2001 (and as further amended, supplemented or
otherwise modified from time to time, the "Credit Agreement"), various Security
Documents (as defined therein), and other instruments executed in connection
therewith (together with the Credit Agreement and Security Documents,
collectively referred to hereinafter as the "Loan Documents," and each as an
individual "Loan Document"); and

       WHEREAS, Borrower anticipates that (i) on or before June 30, 2002, it
will fail to achieve: (a) a Leverage Ratio of less than or equal to 4.50 to 1.0
as required by Section 5.9(a) of the Credit Agreement (the "Leverage Ratio
Default"); (b) an Interest Coverage Ratio of greater than or equal to 2.50 to
1.0 as required by Section 5.9(c) of the Credit Agreement (the "Interest
Coverage Ratio Default"); and (c) a Fixed Charge Coverage Ratio of greater than
or equal to 1.05 to 1.0 as required by Section 5.9(e) of the Credit Agreement
(the "Fixed Charge Coverage Ratio Default") and (ii) it may default in certain
other obligations under the Credit Agreement as set forth on Exhibit A to this
Agreement (the "Exhibit A Defaults") (collectively, the Leverage Ratio Default,
the Interest Coverage Ratio Default, the Fixed Charge Coverage Ratio Default and
the Exhibit A Defaults are hereinafter collectively referred to as the
"Anticipated Defaults," and each as an individual "Anticipated Default"); and

       WHEREAS, Agent and Required Lenders are willing to forbear from enforcing
their rights arising because of the Anticipated Defaults and other defaults
specified herein until the Termination Date (as defined below) on the terms and
conditions specified in this Agreement; and

       WHEREAS, Agent and Required Lenders have agreed to the amendments to the
Credit Agreement as set forth herein; and

       WHEREAS, the outstanding Indebtedness owing under the Credit Agreement
totals the amounts set forth on "Exhibit B" to this Agreement, plus costs,
expenses and other fees and

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charges as provided in the Credit Agreement and the other Loan Documents (all
such amounts are hereinafter collectively referred to as the "Current
Obligations").

       NOW, THEREFORE, for good and valuable consideration, the receipt and
sufficiency of which are hereby acknowledged, the parties hereto hereby agree as
follows:

                             SECTION 1. DEFINITIONS

       1.1 All capitalized terms used herein and not otherwise defined herein
shall have the meanings assigned to such terms in the Credit Agreement.

       1.2 The following terms used in this Agreement shall have the meanings
set forth below:

       "Forbearance Default" means any one the following: (a) the occurrence of
any Default or Event of Default (other than the Anticipated Defaults and the
default caused by Borrower's failure to make its July 15, 2002 interest payment
pursuant to the Subordinated Debt Documents, if any the "Sub Debt Payment")
under the Credit Agreement; (b) the failure of Borrower or any Guarantor to
comply with any term, condition or covenant set forth in this Agreement; (c) any
representation made by Borrower or any Guarantor under or in connection with
this Agreement shall have been materially false or misleading as of the date
when made; (d) the filing of any petition (voluntary or involuntary) under the
insolvency or bankruptcy laws of the United States or any state with respect to
Borrower or any Guarantor or any of their respective affiliates or Subsidiaries;
provided however, that the filing of an involuntary petition shall not be a
Forbearance Default unless such petition shall not be dismissed or stayed for a
period of ten (10) days or more from the date of filing the petition, or an
order for relief shall have been entered; (e) Borrower or any Guarantor makes a
payment in respect of the Subordinated Debt; or (f) any holder of the
Subordinated Debt (or any agent or representative of such holder), institutes an
action or proceeding to collect or otherwise realize upon the Subordinated Debt
and such action or proceeding shall not be dismissed, stayed or bonded for a
period of twenty (20) days or more after the date of initiation of the action or
proceeding

       "Termination Date" means the earliest to occur of (a) 5:00 p.m. Eastern
Standard time on August 13, 2002, or (b) the date upon which a Forbearance
Default occurs.

                        SECTION 2. AGREEMENT TO FORBEAR

       2.1 Provided that no Forbearance Default occurs, Agent and Lenders hereby
agree to forbear and refrain, through the Termination Date, from exercising
their respective rights and remedies under the Credit Agreement or any other
Loan Document that may exist because of the Anticipated Defaults or a default
respecting the Sub Debt Payment.

       2.2 Nothing in this Agreement shall be construed as a waiver of the
Anticipated Defaults, which defaults shall continue in existence subject only to
the agreement of Agent and Lenders, upon the occurrence of such Anticipated
Defaults as set forth herein, not to enforce their respective rights and
remedies for a limited period of time as set forth herein. Notwithstanding the
preceding sentence (and without in any manner limiting the generality or the
specific thereof), the occurrence of any Anticipated Defaults or other defaults
identified herein shall only become

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Defaults or Events of Defaults for purposes of the Credit Agreement on the
Termination Date. Except as expressly provided herein, the execution and
delivery of this Agreement shall not: (a) constitute an amendment, extension,
modification, or waiver of any aspect of the Credit Agreement or the other Loan
Documents; (b) extend the terms of the Credit Agreement or the due date of any
of the Obligations; (c) give rise to any obligation on the part of Agent or
Lenders to extend, modify or waive any term or condition of the Credit Agreement
or any of the other Loan Documents; or (d) give rise to any defenses or
counterclaims to the right of Agent and Lenders to compel payment of the
Obligations or to otherwise enforce their respective rights and remedies under
the Credit Agreement and the other Loan Documents. Except as expressly limited
herein, Agent and Lenders hereby expressly reserve all of their respective
rights and remedies under the Loan Documents and under applicable law with
respect to such Anticipated Defaults. Borrower and each Guarantor expressly
acknowledge that from and after the Termination Date, Agent and Lenders shall be
entitled to enforce the Loan Documents and require strict compliance with all of
the terms and provisions of the Credit Agreement and the other Loan Documents.

                 SECTION 3. AMENDMENTS TO THE CREDIT AGREEMENT

         The Credit Agreement is hereby amended as follows:

       3.1 Amendment to Article I of the Credit Agreement. Section 1.1 of the
Credit Agreement, "Defined Terms" is hereby modified and amended as follows:

              (a) The following defined terms are hereby modified and amended as
   follows:

                  (1) Amendment to the definition of "Interest Period."
   Subsections (i) and (ii) of the definition of "Interest Period" are hereby
   modified and amended by deleting the references to "one, two, three or six
   months" set forth therein and substituting "thirty days" therefor.

                  (2) Amendment to the definition of "Interest Payment Date."
   The definition of "Interest Payment Date" is hereby modified and amended by
   deleting the existing definition in its entirety and substituting the
   following therefor:

                  ""Interest Payment Date" shall mean (a) as to any Alternate
   Base Rate Loan or Swingline Loan, the last day of each month in arrears and
   on the applicable Maturity Date, and (b) as to any LIBOR Rate Loan, the last
   day of such Interest Period."

                  (3) Amendment to the definition of "Permitted Investments."
   The definition of "Permitted Investments" is hereby modified and amended by
   deleting subsection (iv) thereof in its entirety and substituting the
   following therefor:

                      "(iv) loans and advances to officers, directors, employees
and Affiliates in an aggregate amount not to exceed $100,000 at any time
outstanding;"

              (b) The following defined terms are hereby inserted in the
   appropriate alphabetical order:

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                  (1) ""Fourth Amendment" shall mean that certain Fourth
   Amendment to Credit Agreement and Forbearance Agreement dated as of June 28,
   2002 by and among the Borrower, the Guarantors identified therein, the
   Lenders identified therein and the Agent.

                  (2) "Fourth Amendment Effective Date" shall mean the Agreement
   Effective Date as defined in the Fourth Amendment.

                  (3) "Fourth Amendment Termination Date" shall mean the
   Termination Date as defined in the Fourth Amendment."

       3.2 Amendment to Article II of the Credit Agreement. Section 2.1(a) of
the Credit Agreement "Revolving Loans" (as amended) is hereby further modified
and amended by deleting the last paragraph thereof in its entirety and
substituting the following therefor:

              "Notwithstanding anything to the contrary contained herein, in no
event shall the Borrower be permitted to borrow Revolving Loans in a principal
amount greater than $45,000,000 (the "Borrowing Cap") until the earlier of (a)
the Fourth Amendment Termination Date; provided, however, that after the Fourth
Amendment Termination Date, the Borrowing Cap shall not exceed $50,000,000, or
(b) the date upon which Borrower has demonstrated to the satisfaction of the
Agent that Borrower is in compliance with all of the financial covenants set
forth in Section 5.9 hereof, as such Section 5.9 was in effect on September 30,
1998 without giving effect to any subsequent amendments thereto, and upon such
compliance date the Borrowing Cap shall terminate."

       3.3 Amendment to Article VI of the Credit Agreement. Article VI of the
Credit Agreement "Negative Covenants" is hereby modified and amended as follows:

               (a) The following section is added to the existing negative
   covenants:

                   "Section 6.16 Limitation on Capital Expenditures. The
   Borrower will not, nor will it permit its Subsidiaries to, make Capital
   Expenditures in excess of $500,000 in the aggregate during the period from
   the Fourth Amendment Effective Date to the Fourth Amendment Termination
   Date."

               (b) The following sections are hereby amended and modified as
   follows:

                  (1)  Section 6.1 "Indebtedness."

                        (i)  Section 6.1 (c) is hereby deleted in its entirety
                             and the following substituted therefor:

                                  "(c) Indebtedness incurred after the Closing
                             Date and prior to the Fourth Amendment Effective
                             Date consisting of Capital Leases or Indebtedness
                             incurred to provide all or a portion of the
                             purchase price or cost of construction of an asset
                             provided that (i) such Indebtedness when incurred
                             shall not exceed the purchase price or cost of
                             construction of such asset; (ii) no such
                             Indebtedness shall be refinanced for a principal
                             amount in excess of the principal balance
                             outstanding thereon at the time of such
                             refinancing; and (iii) the total amount of all such

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                             Indebtedness shall not exceed $10,000,000 at any
                             time outstanding;"

                       (ii)  Section 6.1 (e) is hereby deleted in its entirety
                             and the following is substituted therefor:

                                  "(e) Indebtedness and obligations owing under
                             Hedging Agreements relating to the Loans hereunder
                             and other Hedging Agreements entered into in order
                             to manage existing or anticipated interest rate,
                             exchange rate or commodity price risks and not for
                             speculative purposes; provided that the aggregate
                             notional amount of all such Hedging Agreements
                             relating solely to foreign currency exchange
                             agreements or currency protection agreements,
                             including any renewals or roll-overs thereof, shall
                             not exceed $15,000,000 at any time."

                  (2) Section 6.5 "Consolidation, Merger, Sale or Purchase of
   Assets, etc." Section 6.5(a)(v) is hereby deleted in its entirety and the
   following substituted therefor: "(v) [Intentionally Omitted]."

                  (3) Section 6.15 "Bank Accounts" is hereby deleted in its
   entirety and the following substituted therefor:

                      "Section 6.15 Bank Accounts. The Borrower will not, nor
                  will it permit any Subsidiary to, open, maintain or otherwise
                  have any checking, savings or other accounts at any bank or
                  other financial institution other than (a) any such accounts
                  maintained with a Lender; provided that, the aggregate
                  collected balance on deposit in all such accounts maintained
                  in the United States at any time with respect to all Lenders
                  shall not exceed $1,500,000, and (b) any such accounts
                  maintained with one or more European financial institutions;
                  provided that, the aggregate collected balance on deposit in
                  all such accounts at any time with respect to all such
                  European institutions shall not exceed $2,500,000."

       3.4 Amendment to Article IX of the Credit Agreement. Section 9.2
"Notices" is hereby modified and amended by deleting Section 9.2 thereof in its
entirety and substituting the following thereof:

            "Except as otherwise provided in Artlcle II, all notices, requests
and demands to or upon the respective parties hereto to be effective shall be in
writing (including by telecopy), and, unless otherwise expressly provided
herein, shall be deemed to have been duly given or made (a) when delivered by
hand, (b) when transmitted via telecopy (or other facsimile device) to the
number set out herein, (c) the day following the day on which the same has been
delivered prepaid to a reputable national overnight air courier service, or (d)
the third Business Day following the day on which the same is sent by certified
or registered mail, postage prepaid, in each case, addressed as follows in the
case of the Borrower, the other Credit Parties and the

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Agent, and as set forth on Schedule 9.2 in the case of the Lenders, or to such
other address as may be hereafter notified by the respective parties hereto and
any future holders of the Notes:

      The Borrower                         Advanced Glassfiber Yarns LLC
      and the other                        2556 Wagener Road
      Credit Parties:                      Aiken, South Carolina 29801
                                           Attention: Robert Pistole, President
                                           Telecopier: (803) 643-1424
                                           Telephone:  (803) 643-1560

                                           with a copy to:

                                           Owens Corning World Headquarters
                                           One Owens Corning Parkway
                                           Toledo, Ohio 43659
                                           Telecopier: (419) 248-1723
                                           Telephone:  (419) 248-8000

                                           BGF Industries, Inc.
                                           3802 Robert Porcher Way
                                           Greensboro, North Carolina 27410
                                           Attention: Philippe Dorier,
                                           Telecopier: (336) 545-7715
                                           Telephone:  (336) 545-0011

                                           Proskauer Rose LLP
                                           1585 Broadway
                                           New York, New York 10036
                                           Attention: Alan B. Hyman, Esq.
                                           Telecopier: (212) 969-2900
                                           Telephone:  (212) 969-3275

      The Agent:                           Wachovia Securities
                                           191 Peachtree Street, NE
                                           Atlanta, Georgia 30303
                                           Attention: Reginald T. Dawson,
                                            Senior Vice President
                                           Telecopier: (404) 332-6920
                                           Telephone:  (404) 332-4075

                                           with a copy to:

                                           Paul, Hastings, Janofsky & Walker LLP
                                           600 Peachtree Street, NE

<PAGE>

                                           Suite 2400
                                           Atlanta, Georgia 30308
                                           Attention: Jesse H. Austin, III, Esq.
                                           Telecopier: (404) 815-2424
                                           Telephone:  (404) 815-2208"



                    SECTION 4. REPRESENTATIONS AND WARRANTIES

         In consideration of the limited agreement of Agent and Lenders to amend
the Credit Agreement and forbear from the exercise of their rights and remedies
as set forth above, Borrower and each Guarantor hereby represent and warrant in
favor of Agent and each Lender as follows:

         4.1 Borrower and each Guarantor have the corporate or limited liability
power and authority (a) to enter into this Agreement, and (b) to do all acts and
things as are required or contemplated hereunder to be done, observed and
performed by them, respectively;

         4.2 This Agreement has been duly authorized, validly executed and
delivered by one or more authorized signatories of Borrower and each Guarantor
and constitutes the legal, valid and binding obligation of Borrower and each
Guarantor, enforceable against Borrower and each Guarantor in accordance with
its terms;

         4.3 The execution and delivery of this Agreement and performance by
Borrower and each Guarantor does not and will not require the consent or
approval of any regulatory authority or governmental authority or agency having
jurisdiction over Borrower or any Guarantor that has not already been obtained,
nor contravene or conflict with the formation, charter or organizational
documents of Borrower or any Guarantor, or the provisions of any statute,
judgment or order to which Borrower or any Guarantor is a party or by which any
of their respective properties are or may become bound;

         4.4 As of the Agreement Effective Date (defined below), and after
giving effect to this Agreement (a) except as specified herein, no Default or
Event of Default exists under the Credit Agreement, and (b) except as set forth
on Exhibit A to this Agreement, each representation and warranty set forth in
Article 3 of the Credit Agreement is true and correct; and

         4.5 All Loan Documents to which Borrower and each Guarantor are a
party, including without limitation, the Credit Agreement, constitute valid and
legally binding obligations of Borrower and each Guarantor enforceable against
Borrower and such Guarantor in accordance with the terms thereof.

                       SECTION 5. COVENANTS AND AGREEMENTS

         In order to induce Agent and Lenders to forbear from the exercise of
their respective rights and remedies as set forth above, Borrower hereby
covenants and agrees as follows:

<PAGE>

         5.1 Borrower will refrain from paying its July 15, 2002 regularly
scheduled interest payment, or any other payment then due in respect of the
Subordinated Debt.

         5.2 The Borrower shall pay to Agent a fee equal to 0.125% multiplied by
the aggregate Commitments as of the date hereof for the account of each Lender
pro rata according to such lender's aggregate Commitment as of the date hereof;
provided, however, that such fee shall be payable only to those Lenders that
shall have returned executed signature pages to this Agreement not later than
5:00 p.m. on June 26, 2002 as directed by Agent. Such fee shall be fully earned
and non-refundable on the effective date of this Agreement.

         5.3 In addition to financial reports and other certificates and
instruments Borrower is required to deliver to Agent pursuant to Sections 5.1
and 5.2 of the Credit Agreement, Borrower shall deliver to Agent, (a) on a
weekly basis by not later than Friday of each week, a rolling 13-week cash flow
projection, together with a comparison of actual payments to budgeted line items
for the prior weekly period, in form and substance satisfactory to Agent, and
(b) such other reports, analyses, financial statements and projections as Agent
may reasonably request from time to time.

         5.4 The Borrower will not modify or otherwise change any provisions of
any Material Contract (exclusive of collective bargaining agreements) during the
term of this Agreement, specifically including any contracts or agreements
between the Borrower or any of its Subsidiaries, on the one hand, and, on the
other hand, any members of the Borrower or any of their subsidiaries and any
members or shareholders of GHC Sub, Glass Holdings, Jefferson, or Owens Corning,
or Owens Corning in its individual corporate capacity.

         5.5 Borrower shall, at Borrower's expense, and shall cause the
Guarantors to, cooperate fully, and cause their respective officers, employees,
accountants, consultants and other agents to cooperate fully, in furnishing
information as and when reasonably requested by Agent regarding, without
limitation, the business plan delivered to Agent on June 11, 2002, other
financial reports, business plans and projections delivered to Agent from time
to time, the Collateral, and Borrower's or any Guarantor's affairs, finances,
financial condition and business operations. Borrower and each Guarantor
authorize Agent to meet and/or have discussions with any of Borrower's or such
Guarantor's officers, key employees, accountants, consultants, financial
advisors, and other agents from time to time to discuss any reasonable matters
regarding business plans, financial reports, projections, and the Collateral and
Borrower's or such Guarantor's affairs, finances, financial condition and
business operations, and shall direct and authorize all such persons and
entities to fully disclose to Agent all information reasonably requested by
Agent subject to all applicable attorney-client or accountant-client privileges.
Borrower shall promptly, when and as requested by Agent, provide Agent with
access to Borrower's original books and records and permit Agent to make copies
thereof subject to all applicable attorney-client or accountant-client
privileges.

         5.6 Borrower shall, throughout the term of this Agreement, continue to
make a full and complete disclosure of all material aspects of its financial
condition and business operations on behalf of itself and each Guarantor.

<PAGE>

         5.7 Borrower shall continue to perform and observe all terms and
conditions contained in the Loan Documents that are not specifically mentioned
in this Agreement as an Anticipated Default or a default relating to the Sub
Debt Payment.

         5.8 This Agreement is intended to be a further accommodation by Agent
and Lenders to Borrower. In consideration of all such accommodations, and
acknowledging that Agent and Lenders will be specifically relying on the
following provisions as a material inducement in entering into this Agreement,
Borrower agrees that in connection with such release and discharge, Borrower
specifically and expressly waives all claims which Borrower does not know or
suspect to exist in its favor at the time of executing this Agreement.

                            SECTION 6. MISCELLANEOUS

         6.1 ACKNOWLEDGMENT OF VALIDITY, ENFORCEABILITY OF LOAN DOCUMENTS AND
RELEASE. (a) To the extent of any inconsistencies between the terms and
provisions of this Agreement and the terms and provisions of the Credit
Agreement and other Loan Documents, this Agreement shall govern. In all other
respects, the Credit Agreement and other Loan Documents shall remain in full
force and effect. Borrower and each Guarantor expressly acknowledge and agree
that the Credit Agreement and other Loan Documents are valid and enforceable by
Agent and Lenders, and expressly reaffirm each of their obligations (including
the amount of the Current Obligations) under the Credit Agreement and other Loan
Documents, free and clear of all defenses, offsets and counterclaims of any kind
or nature. Borrower and each Guarantor further expressly acknowledge and agree
that Agent, for its benefit and the benefit of the Lenders, has a valid, duly
perfected and fully enforceable security interest in and lien against the
Collateral. Borrower and each Guarantor agree that they shall not dispute the
validity or enforceability of the Credit Agreement and other Loan Documents or
any of their respective obligations thereunder, or the validity, priority,
enforceability or extent of Agent's security interest in or lien against any
item of Collateral.

                  (b)   The Borrower and each Guarantor, on behalf of themselves
and any Person claiming by, through, or under the Borrower and each Guarantor,
and each Subsidiary of the Borrower and each Guarantor (if any), on behalf of
themselves and Persons claiming by, through, or under such Subsidiary,
respectively, acknowledges that they have no claim, counterclaim, setoff, action
or cause of action of any kind or nature whatsoever ("Claims") against all or
any of the Agent, the Lenders or any of the Agent's or the Lenders' directors,
officers, employees, agents, attorneys, financial advisors, legal
representatives, successors and assigns (the Agent, the Lenders and their
directors, officers, employees, agents, attorneys, financial advisors, legal
representatives, successors and assigns are jointly and severally referred to as
the "Lender Group"), that directly or indirectly arise out of or are based upon
or in any manner connected with any "Prior Event" (as defined below), and the
Borrower, the Guarantors and each Subsidiary of the Borrower or the Guarantors
hereby releases the Lender Group from any liability whatsoever should any Claims
nonetheless exist. As used herein the term "Prior Event" means any transaction,
event, circumstances, action, failure to act or occurrence of any sort or type,
whether known or unknown, which occurred, existed, was taken, permitted or begun
prior to the execution of this Agreement and occurred, existed, was taken,
permitted or begun in accordance with, pursuant to or by virtue of any terms of
this Agreement, the transactions referred to herein,

<PAGE>

the Credit Agreement and any Loan Document or oral or written agreement relating
to any of the foregoing, including without limitation any approval or acceptance
given or denied.

      6.2 EXPENSES. Borrower shall reimburse Agent, upon demand, for all fees,
costs and expenses (including, but not limited to, reasonable attorneys' and
consultants' fees, costs and expenses) incurred by Agent in connection with this
Agreement including, but not limited to, such fees, costs and expenses incurred
in connection with the negotiation, drafting, implementation, administration and
enforcement of this Agreement and the other Loan Documents.

      6.3 CONDITIONS PRECEDENT AND EFFECTIVE DATE. This Agreement shall become
effective and be deemed effective upon the Agent's receipt of each of the
following (such date being the "Agreement Effective Date"):

               (a) A counterpart of this Agreement duly executed by Borrower,
each Guarantor, and the Required Lenders; and

               (b) Such other documents executed by Borrower, or as applicable,
any Guarantor, as Agent and Lenders may reasonably require.

      6.4 AMENDMENTS. No amendment or modification of any provision of this
Agreement shall be effective without the written agreement of Agent and the
Required Lenders, and no termination or waiver of any provision of this
Agreement, or consent to any departure therefrom, shall in any event be
effective without the written concurrence of Agent and the Required Lenders. Any
waiver or consent shall be effective only in the specific instance and for the
specific purpose for which it was given.

      6.5 DEFAULT WAIVER. Failure at any time or times hereafter on the part of
Agent or any Lender, to require strict performance by Borrower and each
Guarantor with any provision or term of this Agreement shall not waive, affect
or diminish any right of Agent or the Lenders thereafter to demand strict
compliance and performance therewith. Any suspension or waiver by Agent or the
Lenders of a Default or Event of Default shall not, except as may be expressly
set forth herein, suspend, waive or affect any other Default or Event of
Default, whether the same is prior or subsequent thereto and whether of the same
or of a different kind or character.

      6.6 SOLE BENEFIT OF PARTIES. This Agreement is solely for the benefit of
the parties hereto and their respective successors and assigns, and no other
person or entity shall have any right, benefit or interest under or because of
the existence of this Agreement.

      6.7 SECTION TITLES. The section titles contained in this Agreement are
included for the sake of convenience only, shall be without substantive meaning
or content of any kind whatsoever, and are not a part of the agreement between
the parties.

      6.8 WAIVER BY AGENT AND LENDERS. No course of dealing between Borrower,
any Guarantor, Agent or any Lender and no delay or omission by Agent or any
Lender in exercising any right or remedy under this Agreement or the other Loan
Documents or with respect to the Obligations shall operate as a waiver thereof
or of any other right or remedy, and no single or

<PAGE>

partial exercise thereof shall preclude any other or further exercise thereof or
the exercise of any other right or remedy. All rights and remedies of Agent and
Lenders are cumulative.

     6.9  SEVERABILITY. The provisions of this Agreement are independent of and
separable from each other, and no such provision shall be affected or rendered
invalid or unenforceable by virtue of the fact that for any reason any other
such provision may be invalid or unenforceable in whole or in part. If any
provision of this Agreement is prohibited or unenforceable in any jurisdiction,
such provision shall be ineffective in such jurisdiction only to the extent of
such provision or unenforceability, and such prohibition or unenforceability
shall not invalidate the balance of such provision to the extent it is not
prohibited or unenforceable nor render prohibited or unenforceable such
provision in any other jurisdiction.

     6.10 ENTIRE AGREEMENT. This Agreement and the other Loan Documents
constitute the entire agreement and understanding between the parties hereto
with respect to the transactions contemplated hereby and supersede all prior
negotiations, understandings and agreements between such parties with respect to
such transactions.

     6.11 APPLICABLE LAW. THIS AGREEMENT AND THE TRANSACTIONS EVIDENCED HEREBY
SHALL BE GOVERNED BY AND CONSTRUED UNDER THE INTERNAL LAWS OF THE STATE OF NORTH
CAROLINA, WITH REGARD TO PRINCIPLES OF CONFLICTS OF LAW, THAT MAY CAUSE THE
APPLICATION OF THE LAWS OF ANOTHER JURISDICTION.

     6.12 CONSENT TO JURISDICTION. THE PARTIES HERETO AND THE OTHER LENDERS
AGREE THAT ANY ACTION OR PROCEEDING TO ENFORCE OR ARISING OUT OF THE LOAN
DOCUMENTS MAY BE COMMENCED IN ANY STATE OR FEDERAL COURT OF COMPETENT
JURISDICTION IN THE STATE OF NORTH CAROLINA, AND THE PARTIES HERETO WAIVE
PERSONAL SERVICE OF PROCESS AND AGREE THAT A SUMMONS AND COMPLAINT COMMENCING AN
ACTION OR PROCEEDING IN ANY SUCH COURT SHALL BE PROPERLY SERVED AND SHALL CONFER
PERSONAL JURISDICTION IF SERVED BY REGISTERED OR CERTIFIED MAIL TO SUCH PARTY,
OR AS OTHERWISE PROVIDED BY THE LAWS OF THE STATE OF NORTH CAROLINA OR THE
UNITED STATES.

     6.13 JURY TRIAL WAIVER. THE PARTIES HERETO HEREBY KNOWINGLY, VOLUNTARILY,
AND INTENTIONALLY WAIVE, TO THE EXTENT PERMITTED BY APPLICABLE LAW, ANY RIGHT TO
TRIAL BY JURY THE PARTIES HERETO MAY HAVE IN ANY ACTION OR PROCEEDING, IN LAW OR
IN EQUITY, IN CONNECTION WITH THE LOAN DOCUMENTS OR THE TRANSACTIONS RELATED
THERETO. THE PARTIES HERETO REPRESENT AND WARRANT THAT NO REPRESENTATIVE OF
AGENT OR ANY LENDER HAS REPRESENTED, EXPRESSLY OR OTHERWISE, THAT SUCH PERSON
WILL NOT, IN THE EVENT OF LITIGATION, SEEK TO ENFORCE THIS RIGHT TO JURY TRIAL
WAIVER. BORROWER AND EACH GUARANTOR ACKNOWLEDGE THAT AGENT AND LENDERS HAVE BEEN
INDUCED TO ENTER INTO THIS AGREEMENT BY, AMONG OTHER THINGS, THE PROVISIONS OF
THIS SECTION.

<PAGE>

     6.14 WAIVER OF BOND. BORROWER AND EACH GUARANTOR HEREBY WAIVE THE POSTING
OF ANY BOND OTHERWISE REQUIRED OF AGENT OR ANY LENDER IN CONNECTION WITH ANY
JUDICIAL PROCESS OR PROCEEDING OR TO ENFORCE ANY JUDGMENT OR OTHER COURT ORDER
ENTERED IN FAVOR OF AGENT OR ANY LENDER OR TO ENFORCE BY SPECIFIC PERFORMANCE,
ANY TEMPORARY RESTRAINING ORDER, PRELIMINARY OR PERMANENT INJUNCTION, OR THIS
AGREEMENT.

     6.15 CONSULTATION WITH COUNSEL. THE PARTIES HERETO REPRESENT TO AGENT AND
LENDERS THAT THEY HAVE DISCUSSED THIS AGREEMENT WITH THEIR LAWYERS.

     6.16 COUNTERPARTS. This Agreement may be executed in any number of
counterparts, each of which shall be deemed an original but all of which
together shall constitute one and the same instrument. Delivery of an executed
counterpart of this Agreement by facsimile transmission shall be equally
effective as a manually delivered executed counterpart hereof.

     [Signature on next page - remainder of page intentionally left blank.]

<PAGE>

                                    EXHIBIT A

                           Other Anticipated Defaults

Borrower believes that it may default on the following provisions of the Loan
Documents:

     1.  The representation in Section 3.5 of the Credit Agreement would not be
         true and correct with respect to the defaults identified in this
         Agreement.
     2.  The representation in Section 3.17 of the Credit Agreement may not be
         true and correct.
     3.  Pursuant to Section 5.15 of the Credit Agreement, delivery to Agent and
         each of the Lenders, by July 5, 2002, of quarterly financial statements
         demonstrating compliance with the financial ratios identified on the
         first page of this Agreement.
     4.  Various Events of Default in Section 7.1 of the Credit Agreement may
         occur to the extent of the defaults identified in this Agreement.

<PAGE>

                                    EXHIBIT B

                               Current Obligations

                                                          Outstanding Principal
                                                          ---------------------
                                                             (as of 6/17/02)

Revolving Loans                                           $ 31,494,388.65
         Revolver                                           28,000,000.00
         Swingline Loans                                     1,200,000.00
         Interest                                               68,033.65
         Face Amount of Letters of Credit                    2,226,355.00


Tranche A Term Loan                                         56,846,245.92
         Interest                                              741,843.51


Tranche B Term Loan                                         95,150,324.62
         Interest                                            1,402,277.91
                                                          ---------------


Total Outstanding Principal and Interest on all Loans     $185,635,080.61

<PAGE>

         IN WITNESS WHEREOF, the parties hereto have caused this Agreement to be
executed as of the date first set forth above, by their respective duly
authorized officers.

BORROWER:                              ADVANCED GLASSFIBER YARNS,
                                       LLC, a Delaware limited liability company



                                       By:    /s/ Catherine Cuisson
                                          --------------------------------------
                                       Name:  Catherine Cuisson
                                       Title: Chief Financial Officer and VP



GUARANTORS:                            AGY CAPITAL CORP., a Delaware corporation



                                       By:    /s/ Catherine Cuisson
                                          --------------------------------------
                                       Name:  Catherine Cuisson
                                       Title: Chief Financial Officer and VP



AGENT AND LENDERS:                     WACHOVIA BANK, NATIONAL
                                       ASSOCIATION (f/k/a First Union National
                                       Bank, a national banking association), as
                                       Agent and a Lender



                                       By:    /s/ Reginald T. Dawson
                                          --------------------------------------
                                       Name:  Reginald T. Dawson
                                       Title: Director



                                       NATEXIS BANQUES POPULAIRES, as a Lender

                                       By:    /ss/
                                          --------------------------------------
                                       Name:
                                       Title: President and Manager
                                       Multinational Group

<PAGE>

                                          By:     /s/ Christine Dirringer
                                             --------------------------------
                                          Name:  Christine Dirringer
                                          Title: Vice President


                                          CREDIT LYONNAIS, NEW YORK
                                          BRANCH, as a Lender


                                          By:     /s/ Monique Benhamou
                                             --------------------------------
                                          Name:  Monique Benhamou
                                          Title: Vice President


                                          SOCIETE GENERALE, as a Lender


                                          By:     /s/ Marc J. Pouget-Abadie
                                             --------------------------------
                                          Name:  Marc J. Pouget-Abadie
                                          Title: Vice President

                                          ALLSTATE LIFE INSURANCE
                                          COMPANY, as a Lender


                                          By:     /s/ Jerry D. Zinkula
                                             --------------------------------
                                          Name:  Jerry D. Zinkula

                                          By:     /s/ Ronald Mendel
                                             --------------------------------
                                          Name:  Ronald Mendel
                                          Title: Authorized Signatorian


                                          SEQUILS-ING I (HBDGM), LTD. as a
                                          Lender


                                          By:  ING Capital Advisors LLC, as
                                          Collateral Manager


<PAGE>

                                          By:     /s/ Philip C. Robbins
                                             --------------------------------
                                          Name:  Philip C. Robbins
                                          Title: Vice President


                                          ARCHIMEDES FUNDING III, LTD., as
                                          a Lender

                                          By:  ING Capital Advisors LLC, as
                                          Collateral Manager


                                          By:     /s/ Philip C. Robbins
                                             --------------------------------
                                          Name:  Philip C. Robbins
                                          Title: Vice President


                                          ELC (CAYMAN) LTD. 1999-III, as a
                                          Lender


                                          By: David L. Babson & Company, Inc. as
                                          Collateral Manager

                                          By:     /s/ Glenn Duffy
                                             --------------------------------
                                          Name:  Glenn Duffy
                                          Title: Managing Director


                                          ELC (CAYMAN) LTD., as a Lender


                                          By: David L. Babson & Company, Inc. as
                                          Collateral Manager

                                          By:     /s/ Glenn Duffy
                                             --------------------------------
                                          Name:  Glenn Duffy
                                          Title: Managing Director


<PAGE>

                                          ELC (CAYMAN) LTD. 2000-I, as a
                                          Lender


                                          By: David L. Babson & Company, Inc. as
                                          Collateral Manager

                                          By:     /s/ Glenn Duffy
                                             --------------------------------
                                          Name:  Glenn Duffy
                                          Title: Managing Director


                                          ERSTE BANK NEW YORK BRANCH,
                                          as a Lender


                                          By:     /s/ Paul Judicke
                                             --------------------------------
                                          Name:  Paul Judicke
                                          Title: Vice President


                                          By:     /s/ John Runnion
                                             --------------------------------
                                          Name:  John Runnion
                                          Title: Managing Director


                                          THE CIT GROUP/EQUIPMENT
                                          FINANCING, INC., as a Lender


                                          By:     /s/ W.B. Stoebig
                                             --------------------------------
                                          Name:  W.B. Stoebig
                                          Title: Vice President - Credit


                                          TORONTO DOMINION (NEW YORK),
                                          INC., as a Lender


                                          By:     /s/ Susan K. Strong
                                             --------------------------------
                                          Name:  Susan Strong
                                          Title: Vice President

<PAGE>

                                          SANKATY HIGH YIELD PARTNERS
                                          II, L.P., as a Lender


                                          By:     /s/ Diane J. Exter
                                             --------------------------------
                                          Name:  Diane J. Exter
                                          Title: Managing Director,
                                                 Portfolio Manager


                                          SANKATY HIGH YIELD PARTNERS
                                          III, L.P., as a Lender


                                          By:     /s/ Diane J. Exter
                                             --------------------------------
                                          Name:  Diane J. Exter
                                          Title: Managing Director
                                                 Portfolio Manager


                                          ABN AMRO, as a Lender


                                          By:     /s/ Steven C. Wimpenny
                                             --------------------------------
                                          Name:  Steven C. Wimpenny
                                          Title: Group Senior Vice President

                                          By:     /s/ William J. Teresky, Jr.
                                             --------------------------------
                                          Name:  William J. Teresky, Jr.
                                          Title: Group Vice President


                                          ALLIANCE CAPITAL MANAGEMENT L.P.,
                                          as Manager on behalf of Alliance
                                          Capital Funding, LLC, as Assignee


                                          By:  ALLIANCE CAPITAL MANAGEMENT
                                          CORPORATION, general partner of
                                          Alliance Capital Management L.P.



<PAGE>

                                          By:     /s/ Michael E. Sohr
                                             --------------------------------
                                          Name:  Michael E. Sohr
                                          Title: Vice President


                                          CREDIT INDUSTRIEL ET
                                          COMMERCIAL, as a Lender


                                          By:     /s/ Eric Longuet
                                             --------------------------------
                                          Name:  Eric Longuet
                                          Title: Vice President


                                          By:     /s/ Frederic Landriot
                                             --------------------------------
                                          Name:  Frederic Landriot
                                          Title: Assistant Vice President

                                          PB (USA) CAPITAL CORPORATION,
                                          as a Lender


                                          By:     /s/ Andrew L. Shipman
                                             --------------------------------
                                          Name:  Andrew L. Shipman
                                          Title: Assistant Vice President


                                          By:     /s/ Jeffrey Frost
                                             --------------------------------
                                          Name:  Jeffrey Frost
                                          Title: Managing Director
                                                 Portofolio Management


                                          SUNTRUST BANK, as a Lender


                                          By:     /s/ Steven J. Newby
                                             --------------------------------
                                          Name:  Steven J. Newby
                                          Title: Director

<PAGE>

                                                MORGAN STANLEY PRIME INCOME
                                                TRUST, as a Lender



                                                By:     /s/
                                                   -----------------------------
                                                Name:
                                                Title:  Vice President



                                                FIRSTRUST BANK, as a Lender



                                                By:     /s/ Kent Nelson
                                                   -----------------------------
                                                Name:   Kent Nelson
                                                Title:  Senior Vice President



                                                SENIOR DEBT PORTFOLIO, as a
                                                Lender

                                                By: Boston Management and
                                                Research as Investment Advisor



                                                By:     /s/ Payson F. Swaffield
                                                   -----------------------------
                                                Name:   Payson F. Swaffield
                                                Title:  Vice President



                                                EATON VANCE SENIOR INCOME TRUST,
                                                as a Lender

                                                By: Eaton Vance Management as
                                                Investment Advisor



                                                By:     /s/ Payson F. Swaffield
                                                   -----------------------------
                                                Name:   Payson F. Swaffield
                                                Title:  Vice President

<PAGE>

                                                EATON VANCE INSTITUTIONAL SENIOR
                                                LOAN FUND, as a Lender

                                                By: Eaton Vance Management as
                                                Investment Advisor



                                                By:     /s/ Payson F. Swaffield
                                                   -----------------------------
                                                Name:   Payson F. Swaffield
                                                Title:  Vice President



                                                OXFORD STRATEGIC INCOME FUND,
                                                as a Lender

                                                By: Eaton Vance Management as
                                                Investment Advisor



                                                By:     /s/ Payson F. Swaffield
                                                   -----------------------------
                                                Name:   Payson F. Swaffield
                                                Title:  Vice President



                                                EATON VANCE CDO III, LTD., as a
                                                Lender

                                                By: Eaton Vance Management as
                                                Investment Advisor



                                                By:     /s/ Payson F. Swaffield
                                                   -----------------------------
                                                Name:   Payson F. Swaffield
                                                Title:  Vice President



                                                GRAYSON & CO., as a Lender

                                                By: Boston Management and
                                                Research as Investment Advisor



                                                By:     /s/ Payson F. Swaffield
                                                   -----------------------------
                                                Name:   Payson F. Swaffield
                                                Title:  Vice President

<PAGE>

                                           SOMERS CDO, LIMITED, as a Lender

                                           By: David L. Babson and Company
                                           Incorporated, under delegated
                                           authority from Massachusetts Mutual
                                           Life Insurance Company, its
                                           Collateral Manager



                                           By:    /s/ Mary Ann McCarthy
                                              ----------------------------------
                                           Name:  Mary Ann McCarthy
                                           Title: Managing Director



                                           MASSMUTUAL HIGH YIELD PARTNERS II,
                                           LLC, as a Lender

                                           By: HYP Management Inc., as Managing
                                           Partner



                                           By:    /s/ Mary Ann McCarthy
                                              ----------------------------------
                                           Name:  Mary Ann McCarthy
                                           Title: Vice President



                                           MASSACHUSETTS MUTUAL LIFE INSURANCE
                                           COMPANY, as a Lender

                                           By: David L. Babson and Company
                                           Incorporated, under delegated
                                           authority from Massachusetts Mutual
                                           Life Insurance Company, its
                                           Collateral Manager

                                           By:    /s/ Mary Ann McCarthy
                                              ----------------------------------
                                           Name:  Mary Ann McCarthy
                                           Title: Vice President



                                           KZH ING-1 LLC, as a Lender

                                           By: ING Capital Advisors LLC, as
                                           Collateral Management

                                           By:    /s/ Philip C. Robbins
                                              ----------------------------------
                                           Name:  Philip C. Robbins
                                           Title: Vice President

<PAGE>

                                           KZH ING-2 LLC, as a Lender



                                           By:    /s/ Susan Lee
                                              ----------------------------------
                                           Name:  Susan Lee
                                           Title: Authorized Agent



                                           KZH ING-3 LLC, as a Lender

                                           By: ING Capital Advisors LLC, as
                                           Collaterol Management



                                           By:    /s/ Philip C. Robbins
                                              ----------------------------------
                                           Name:  Philip C. Robbins
                                           Title: Vice President



                                           BANK OF AMERICA, N.A., as a Lender



                                           By: _____________________________

                                           Name: __________________________

                                           Title: ___________________________