LETTER TO REGISTERED HOLDERS AND DTC PARTICIPANTS
                REGARDING THE TENDER OF ANY AND ALL OUTSTANDING
              SERIES A 10 3/8% SENIOR SUBORDINATED NOTES DUE 2008
                                       OF
                                 TRANSDIGM INC.
              PURSUANT TO THE PROSPECTUS DATED             , 2002

        THE EXCHANGE OFFER AND WITHDRAWAL RIGHTS WILL EXPIRE AT 5:00 P.M.,
NEW YORK CITY TIME, ON       , 2002, UNLESS EXTENDED (THE "EXPIRATION DATE").

                                                                          , 2002

To Registered Holders and DTC Participants:

    TransDigm Inc., a Delaware corporation ("TransDigm") is offering to
exchange, upon and subject to the terms and conditions set forth in the
prospectus, dated             , 2002, and the letter of transmittal, $1,000
principal amount of its 10 3/8% Series B Senior Subordinated Notes due 2008 (the
"Exchange Notes"), which have been registered under the Securities Act of 1933,
as amended, for each $1,000 principal amount of its outstanding 10 3/8%
Series A Senior Subordinated Notes due 2008 (the "Old Notes"), of which
$75,000,000 aggregate principal amount is outstanding.

    In connection with the exchange offer, we are requesting that you contact
your clients for whom you hold Old Notes registered in your name or in the name
of your nominee, or who hold Old Notes registered in their own names. TransDigm
will not pay any fees or commissions to any broker, dealer or other person in
connection with the solicitation of tenders pursuant to the exchange offer.
However, you will, upon request, be reimbursed for reasonable out-of-pocket
expenses incurred in connection with soliciting acceptances of the exchange
offer. TransDigm will pay or cause to be paid all transfer taxes applicable to
the exchange of Old Notes pursuant to the exchange offer, except as set forth in
the prospectus and the letter of transmittal.

    For your information and for forwarding to your clients, we are enclosing
the following documents:

    1.  The prospectus dated             , 2002;

    2.  The letter of transmittal for your use in connection with the tender of
       the Old Notes and for the information of your clients;

    3.  The notice of guaranteed delivery to be used to accept the exchange
       offer if the Old Notes and all other required documents cannot be
       delivered to the exchange agent prior to the Expiration Date; and

    4.  A form of letter which may be sent to your clients for whose account you
       hold Old 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.

    To participate in the exchange offer, a beneficial holder must either:

    -  cause to be delivered to State Street Bank and Trust Company (the
       "exchange agent"), at the address set forth in the letter of transmittal,
       definitive certificated notes representing Old Notes in proper form for
       transfer together with a duly executed and properly completed letter of
       transmittal, with any required signature guarantees and any other
       required documents; or

    -  cause a DTC Participant to tender such holder's Old Notes to the Exchange
       Agent's account maintained at the Depository Trust Company ("DTC") for
       the benefit of the Exchange Agent through DTC's Automated Tender Offer
       Program ("ATOP"), including transmission of a computer-generated message
       that acknowledges and agrees to be bound by the terms of the letter of
       transmittal.

    By complying with DTC's ATOP procedures with respect to the exchange offer,
the DTC Participant confirms on behalf of itself and the beneficial owners of
tendered Old Notes all provisions of the letter of transmittal applicable to it
and such beneficial owners as fully as if it completed, executed and returned
the letter of transmittal to the exchange agent.

    You will need to contact those of your clients for whose account you hold
definitive certificated notes or book-entry interests representing Old Notes and
seek their instructions regarding the exchange offer.

    If holders of Old Notes wish to tender, but it is impracticable for them to
forward their certificates for Old Notes prior to the expiration of the exchange
offer or to comply with the book-entry transfer procedures on a timely basis, a
tender may be effected by following the guaranteed delivery procedures described
in the prospectus and 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
exchange agent for the Old Notes, at its address and telephone number set forth
on the front of the letter of transmittal.

                                          Very truly yours,
                                          TransDigm Inc.

    NOTHING HEREIN OR IN THE ENCLOSED DOCUMENTS SHALL CONSTITUTE YOU OR ANY
OTHER PERSON AS AN AGENT OF TRANSDIGM 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.

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