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          LETTER TO BENEFICIAL HOLDERS REGARDING THE OFFER TO EXCHANGE
  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 Our Clients:

    Enclosed for your consideration is a prospectus, dated       , 2002, of
TransDigm Inc., a Delaware corporation ("TransDigm"), and a letter of
transmittal, that together constitute TransDigm's offer to exchange $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.

    The materials relating to the exchange offer are being forwarded to you as
the beneficial owner of Old Notes carried by us for your account or benefit but
not registered in your name. A tender of any Old Notes may only be made by us as
the registered holder and pursuant to your instructions. Therefore, we urge
beneficial owners of Old Notes registered in the name of a broker, dealer,
commercial bank, trust company or any other nominee to contact such registered
holder promptly if they wish to tender Old Notes in the exchange offer.

    Accordingly, we request instructions as to whether you wish us to tender any
or all such Old Notes held by us for your account or benefit pursuant to the
terms and conditions set forth in the prospectus and the letter of transmittal.
We urge you to read carefully the prospectus and the letter of transmittal and
other material provided herewith before instructing us to tender your Old Notes.
THE LETTER OF TRANSMITTAL IS FURNISHED TO YOU FOR YOUR INFORMATION ONLY AND
CANNOT BE USED BY YOU TO EXCHANGE OLD NOTES HELD BY US FOR YOUR ACCOUNT OR
BENEFIT.

    Your instructions to us should be forwarded as promptly as possible in order
to permit us to tender Old Notes on your behalf in accordance with the
provisions of the exchange offer.

    Your attention is directed to the following:

    1.  The exchange offer will expire at 5:00 p.m., New York City time, on
             , 2002, unless extended. Tendered Old Notes may be withdrawn,
       subject to the procedures described in the prospectus, at any time prior
       to 5:00 p.m. New York City time, on the Expiration Date.

    2.  The Old Notes will be exchanged for the Exchange Notes at the rate of
       $1,000 principal amount of Exchange Notes for each $1,000 principal
       amount of Old Notes validly tendered and not validly withdrawn prior to
       the expiration date. The Exchange Notes will bear interest from the most
       recent interest payment date to which interest has been paid on the Old
       Notes or, if no interest has been paid, from June 1, 2002. The form and
       terms of the Exchange Notes are identical in all material respects to the
       form and terms of the Old Notes, except that the Exchange Notes have been
       registered under the Securities Act of 1933, as amended.

    3.  Notwithstanding any other term of the exchange offer, TransDigm may
       terminate or amend the exchange offer as provided in the prospectus and
       will not be required to accept for exchange, or exchange any Exchange
       Notes for, any Old Notes not accepted for exchange prior to such
       termination.
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    4.  Any transfer taxes applicable to the exchange of the Old Notes pursuant
       to the exchange offer will be paid by TransDigm, except as otherwise
       provided in the prospectus and in Instruction 8 of the letter of
       transmittal.

    5.  Based on an interpretation of the Securities Act by the staff of the
       Securities and Exchange Commission, TransDigm believes that Exchange
       Notes issued pursuant to the exchange offer in exchange for Old Notes may
       be offered for resale, resold and otherwise transferred by holders
       thereof without compliance with the registration and prospectus delivery
       provisions of the Securities Act, provided that the holder:

       (a) is acquiring Exchange Notes in its ordinary course of business;

       (b) is not engaging in and does not intend to engage in a distribution of
           the Exchange Notes;

       (c) is not participating, and has no arrangement or understanding with
           any person to participate, in a distribution of the Exchange Notes;

       (d) is not an "affiliate" of TransDigm or the guarantors, as such term is
           defined under Rule 405 of the Securities Act; and

       (e) the holder is not acting on behalf of any person who could not
           truthfully make these statements.

    To participate in the exchange offer, holders must represent to TransDigm
that each of these statements is true. If the holder is a broker-dealer that
will receive Exchange Notes for its own account in exchange for Old Notes that
were acquired as a result of market-making activities or other trading
activities, it must acknowledge that it will deliver a prospectus meeting the
requirements of the Securities Act in connection with any resale of such
Exchange Notes.

    If you wish to have us tender any or all of your Old Notes, please so
instruct us by completing and returning to us the form entitled "Instruction to
Registered Holders and DTC Participants From Beneficial Owner" that appears
below. An envelope to return your instructions is enclosed. If you authorize a
tender of your Old Notes, the entire principal amount of Old Notes held for your
account will be tendered unless otherwise specified on the instruction form.
Your instructions should be forwarded to us in ample time to permit us to submit
a tender on your behalf by the Expiration Date.

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                     INSTRUCTION TO REGISTERED HOLDERS AND
                                DTC PARTICIPANTS
                            FROM BENEFICIAL OWNER OF
              SERIES A 10 3/8% SENIOR SUBORDINATED NOTES DUE 2008
                                       OF
                                 TRANSDIGM INC.

    The undersigned hereby acknowledges receipt of the prospectus, dated
            , 2002, of TransDigm Inc., a Delaware corporation ("TransDigm"), and
the letter of transmittal, that together constitute TransDigm's offer to
exchange $1,000 principal amount of its Series B 10 3/8% 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 Series A 10 3/8% Senior Subordinated Notes due 2008 (the "Old
Notes"), of which $75,000,000 aggregate principal amount is outstanding.

    This will instruct you, the registered holder and/or book-entry transfer
facility participant, as to the action to be taken by you relating to the
exchange offer with respect to the Old Notes held by you for the account of the
undersigned, upon and subject to the terms and conditions set forth in the
prospectus and the letter of transmittal.

    The aggregate face amount of the Old Notes held by you for the account of
the undersigned is (FILL IN AMOUNT):

    $            of Series A 10 3/8% Senior Subordinated Notes due 2008.

    With respect to the exchange offer, the undersigned hereby instructs you
(check appropriate box):

    / /  To TENDER ALL of the Old Notes held by you for the account of the
         undersigned.

    / /  To TENDER the following Old Notes held by you for the account of the
         undersigned (INSERT PRINCIPAL AMOUNT OF OLD NOTES TO BE TENDERED, IF
         ANY):

    / /  $            of Series A 10 3/8% Senior Subordinated Notes due 2008.

    / /  NOT to TENDER any Old Notes held by you for the account of the
         undersigned.

       - If the undersigned instructs you to tender Old Notes held by you for
         the account of the undersigned, it is understood that you are
         authorized:

       - to make, on behalf of the undersigned (and the undersigned, by its
         signature below, hereby makes to you), the representations and
         warranties and agreements contained in the letter of transmittal that
         are to be made with respect to the undersigned as a beneficial owner,
         including but not limited to the representations, that:

       - the Exchange Notes acquired pursuant to the exchange offer are being
         acquired in the ordinary course of business of the undersigned;

       - the undersigned is not engaging in and does not intend to engage in a
         distribution of the Exchange Notes;

       - the undersigned does not have an arrangement or understanding with any
         person to participate in the distribution of such Exchange Notes;

       - the undersigned is not an "affiliate" of TransDigm or the guarantors
         within the meaning of Rule 405 under the Securities Act of 1933, as
         amended;

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       - if the undersigned is a resident of the State of California, if falls
         under the self-executing institutional investor exemption set forth
         under Section 25102(i) of the Corporate Securities Law of 1968 and
         Rules 260.102.10 and 260.105.14 of the California Blue Sky Regulations;

       - if the undersigned is a resident of the Commonwealth of Pennsylvania,
         it falls under the self-executing institutional investor exemption set
         forth under Sections 203(c), 102(d) and (k) of the Pennsylvania
         Securities Act of 1972, Section 102.111 of the Pennsylvania Blue Sky
         Regulations and an interpretive opinion dated November 16, 1985;

       - the undersigned acknowledges and agrees that any person who is a
         broker-dealer registered under the Securities Exchange Act of 1934, as
         amended, or is participating in the exchange offer for the purpose of
         disturbing the Exchange Notes, must comply with the registration and
         delivery requirements of the Securities Act in connection with a
         secondary resale transaction of the Exchange Notes or interests therein
         acquired by such person and cannot rely on the position of the staff of
         the Securities and Exchange Commission (the "SEC") set forth in certain
         no-action letters;

       - the undersigned and each beneficial owner understands that a secondary
         resale transaction described in the previous bullet point and any
         resales of Exchange Notes or interests therein obtained by such holder
         in exchange for Old Notes or interests therein originally acquired by
         such holder directly from TransDigm should be covered by an effective
         registration statement containing the selling security holder
         information required by Item 507 or Item 508, as applicable, of
         Regulation S-K or the SEC;

       - if the undersigned is a broker-dealer that will receive Exchange Notes
         for its own account in exchange for Old Notes that were acquired as a
         result of market-making activities or other trading activities, it
         acknowledges that it will deliver a prospectus meeting the requirements
         of the Securities Act in connection with any resale of such Exchange
         Notes. By acknowledging that it will deliver and by delivering a
         prospectus meeting the requirements of the Securities Act in connection
         with any resale of such Exchange Notes, the undersigned is not deemed
         to admit that it is an "underwriter" within the meaning of the
         Securities Act; and

       - the undersigned is not acting on behalf of any person who could not
         truthfully make the foregoing representations;

       - to agree, on behalf of the undersigned, as set forth in the letter of
         transmittal; and

       - to take such other action as necessary under the prospectus or the
         letter of transmittal to effect the valid tender of Old Notes. a

    The undersigned acknowledges that if an executed copy of this letter of
transmittal is returned, the entire principal amount of Old Notes held for the
undersigned's account will be tendered unless otherwise specified above.

    The undersigned hereby represents and warrants that the undersigned
(1) owns the notes tendered and is entitled to tender such notes, and (2) has
full power and authority to tender, sell, exchange, assign and transfer the Old
Notes and to acquire Exchange Notes issuable upon the exchange of such tendered
notes, and that, when the same are accepted for exchange, TransDigm will acquire
good, marketable and unencumbered title to the tendered notes, free and clear of
all liens, restrictions, charges and encumbrances and not subject to any adverse
claim or right or restriction or proxy of any kind.

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                                   SIGN HERE

  Name of beneficial owner(s) (please print): __________________________________

  Signature(s): ________________________________________________________________

  Address: _____________________________________________________________________

  Telephone Number. ____________________________________________________________

  Taxpayer Identification Number or Social Security Number: ____________________

  Date: ________________________________________________________________________

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