HEXCEL CORPORATION
                           OFFER FOR ALL OUTSTANDING
                   9 3/4% SENIOR SUBORDINATED NOTES DUE 2009
                                IN EXCHANGE FOR
                   9 3/4% SENIOR SUBORDINATED NOTES DUE 2009,
                        WHICH HAVE BEEN REGISTERED UNDER
                          THE SECURITIES ACT OF 1933,
                                   AS AMENDED
 
To: BROKERS, DEALERS, COMMERCIAL BANKS,
   TRUST COMPANIES AND OTHER NOMINEES:
 
    Hexcel Corporation (the "Company") is offering, upon and subject to the
terms and conditions set forth in the Prospectus, dated            , 1999 (the
"Prospectus"), and the enclosed Letter of Transmittal (the "Letter of
Transmittal"), to exchange (the "Exchange Offer") its 9 3/4% Senior Subordinated
Notes due 2009, which have been registered under the Securities Act of 1933, as
amended, for its outstanding 9 3/4% Senior Subordinated Notes due 2009 (the
"Original Notes"). The Exchange Offer is being made in order to satisfy certain
obligations of the Company contained in the Registration Rights Agreement dated
January 21, 1999, by and among the Company and the initial purchasers referred
to therein.
 
    We are requesting that you contact your clients for whom you hold Original
Notes regarding the Exchange Offer. For your information and for forwarding to
your clients for whom you hold Original Notes registered in your name or in the
name of your nominee, or who hold Original Notes registered in their own names,
we are enclosing the following documents:
 
        1.  Prospectus dated             , 1999;
 
        2.  The Letter of Transmittal for your use and for the information of
    your clients;
 
        3.  A Notice of Guaranteed Delivery to be used to accept the Exchange
    Offer if certificates for Original Notes are not immediately available or
    time will not permit all required documents to reach the Exchange Agent
    prior to the Expiration Date (as defined below) or if the procedure for
    book-entry transfer cannot be completed on a timely basis;
 
        4.  A form of letter which may be sent to your clients for whose account
    you hold Original Notes registered in your name or the name of your nominee,
    with space provided for obtaining such clients' instructions with regard to
    the Exchange Offer;
 
        5.  Guidelines for Certification of Taxpayer Identification Number on
    Substitute Form W-9; and
 
        6.  Return envelopes addressed to The Bank of New York, the Exchange
    Agent for the Exchange Offer.
 
    YOUR PROMPT ACTION IS REQUESTED. THE EXCHANGE OFFER WILL EXPIRE AT 5:00
P.M., NEW YORK CITY TIME, ON            , 1999, UNLESS EXTENDED BY THE COMPANY
(THE "EXPIRATION DATE"). ORIGINAL NOTES TENDERED PURSUANT TO THE EXCHANGE OFFER
MAY BE WITHDRAWN AT ANY TIME BEFORE THE EXPIRATION DATE.
 
    To participate in the Exchange Offer, a duly executed and properly completed
Letter of Transmittal (or facsimile thereof), with any required signature
guarantees and any other required documents, should be sent to the Exchange
Agent and certificates representing the Original Notes should be delivered to
the Exchange Agent, all in accordance with the instructions set forth in the
Letter of Transmittal and the Prospectus.
 
    If a registered holder of Original Notes desires to tender, but such
Original Notes are not immediately available, or time will not permit such
holder's Original Notes or other required documents to reach the

Exchange Agent before the Expiration Date, or the procedure for book-entry
transfer cannot be completed on a timely basis, a tender may be effected by
following the guaranteed delivery procedures described in the Prospectus under
the caption "The Exchange Offer--Guaranteed Delivery Procedures."
 
    The Company will, upon request, reimburse brokers, dealers, commercial banks
and trust companies for reasonable and necessary costs and expenses incurred by
them in forwarding the Prospectus and the related documents to the beneficial
owners of Original Notes held by them as nominee or in a fiduciary capacity. The
Company will pay or cause to be paid all stock transfer taxes applicable to the
exchange of Original Notes pursuant to the Exchange Offer, except as set forth
in Instruction 6 of the Letter of Transmittal.
 
    Any inquiries you may have with respect to the Exchange Offer, or requests
for additional copies of the enclosed materials, should be directed to The Bank
of New York, the Exchange Agent for the Exchange Offer, at its address and
telephone number set forth on the front of the Letter of Transmittal.
 
                                          Very truly yours,
 
                                          HEXCEL CORPORATION
 
    NOTHING HEREIN OR IN THE ENCLOSED DOCUMENTS SHALL CONSTITUTE YOU OR ANY
PERSON AS AN AGENT OF THE COMPANY OR THE EXCHANGE AGENT, OR AUTHORIZE YOU OR ANY
OTHER PERSON TO USE ANY DOCUMENT OR MAKE ANY STATEMENTS ON BEHALF OF EITHER OF
THEM WITH RESPECT TO THE EXCHANGE OFFER, EXCEPT FOR STATEMENTS EXPRESSLY MADE IN
THE PROSPECTUS OR THE LETTER OF TRANSMITTAL.
 
Enclosures
 
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