EXHIBIT 99.4

                       ESTERLINE TECHNOLOGIES CORPORATION

                               LETTER TO CLIENTS
                         FOR TENDER OF ALL OUTSTANDING
                    $175,000,000 7.75% SENIOR NOTES DUE 2013
                                IN EXCHANGE FOR
                                   REGISTERED
                    $175,000,000 7.75% SENIOR NOTES DUE 2013

THE EXCHANGE OFFER WILL EXPIRE AT 5:00 P.M., NEW YORK CITY TIME, ON
            , 2003, UNLESS EXTENDED (THE "EXPIRATION DATE"). NOTES TENDERED IN
SUCH EXCHANGE OFFER MAY BE WITHDRAWN AT ANY TIME PRIOR TO 5:00 P.M., NEW YORK
CITY TIME, ON THE EXPIRATION DATE.

To Our Clients:

     We are enclosing a prospectus dated           , 2003 of Esterline
Technologies Corporation (the "COMPANY") and the related letter of transmittal.
These two documents constitute the Company's offer to exchange its $175,000,000
7.75% Senior Notes due 2013 and the associated guarantees (together, the
"EXCHANGE NOTES"), the issuance of which has been registered under the
Securities Act of 1933, as amended (the "SECURITIES ACT"), for a like principal
amount of its issued and outstanding $175,000,000 7.75% Senior Notes due 2013
and the associated guarantees (the "ORIGINAL NOTES") (together, the "EXCHANGE
OFFER").

     The Exchange Offer for Original Notes is not conditioned upon any minimum
aggregate principal amount of Original Notes being tendered for exchange.

     We are the holder of record of Original Notes held by us for your own
account. A tender of such Original Notes can be made only by us as the record
holder and pursuant to your instructions. The accompanying letter of transmittal
is furnished to you for your information only and cannot be used by you to
tender Original Notes held by us for your account.

     We request instructions as to whether you wish to tender any or all of the
Original Notes held by us for your account pursuant to the terms and conditions
of the Exchange Offer. We also request that you confirm that we may on your
behalf make the representations contained in the letter of transmittal.

     Pursuant to the letter of transmittal, each holder of Original Notes will
represent to the Company that (i) any Exchange Notes received are being acquired
in the ordinary course of business of the person receiving such Exchange Notes,
(ii) such person does not have an arrangement or understanding with any person
to participate in the distribution of the Original Notes or the Exchange Notes
within the meaning of the Securities Act and (iii) such person is not an
"affiliate," as defined in Rule 405 under the Securities Act, of the Company or,
if it is such an affiliate, it will comply with the registration and prospectus
delivery requirements of the Securities Act to the extent applicable. In
addition, each holder of Original Notes will represent to the Company that (i)
if such person is not a broker-dealer, it is not engaged in, and does not intend
to engage in, a distribution of Exchange Notes and (ii) if such person is a
broker-dealer that will receive Exchange Notes for its own account in exchange
for Original Notes that were acquired as a result of market-making activities or
other trading activities, it will deliver a prospectus in connection with any
resale of such Exchange


Notes; however, by so acknowledging and by delivering a prospectus, it will not
be deemed to admit that it is an "underwriter" within the meaning of the
Securities Act.

                                         Very truly yours,

                                        2


PLEASE RETURN YOUR INSTRUCTIONS TO US IN THE ENCLOSED ENVELOPE WITHIN AMPLE TIME
TO PERMIT US TO SUBMIT A TENDER ON YOUR BEHALF PRIOR TO THE APPLICABLE
EXPIRATION DATE.

                    INSTRUCTION TO REGISTERED HOLDER AND/OR
                    BOOK-ENTRY TRANSFER FACILITY PARTICIPANT

To Registered Holder and/or Participant of the DTC:

     The undersigned hereby acknowledges receipt and review of the prospectus
dated           , 2003 of Esterline Technologies Corporation (the "COMPANY") and
the related letter of transmittal. These two documents together constitute the
Company's offer to exchange its $175,000,000 7.75% Senior Notes due 2013 (the
"EXCHANGE NOTES"), the issuance of which has been registered under the
Securities Act of 1933, as amended (the "SECURITIES ACT"), for a like principal
amount of its issued and outstanding $175,000,000 7.75% Senior Notes due 2013
(the "ORIGINAL NOTES") (the "EXCHANGE OFFER").

     This will instruct you, the registered holder and/or DTC participant, as to
the action to be taken by you relating to the Exchange Offer for the Original
Notes held by you for the account of the undersigned.

     The aggregate principal amount of the Original Notes held by you for the
account of the undersigned is:

<Table>
<Caption>
                                                              PRINCIPAL AMOUNT
TITLE OF SERIES                                               (FILL IN AMOUNT)
- ---------------                                               ----------------
                                                           
7.75% Senior Notes due 2013.................................      $
</Table>

     WITH RESPECT TO THE EXCHANGE OFFER, THE UNDERSIGNED HEREBY INSTRUCTS YOU
(CHECK APPROPRIATE BOX):

[ ] TO TENDER ALL ORIGINAL NOTES HELD BY YOU FOR THE ACCOUNT OF THE UNDERSIGNED.

[ ] TO TENDER THE FOLLOWING AMOUNT OF ORIGINAL NOTES HELD BY YOU FOR THE ACCOUNT
    OF THE UNDERSIGNED:

<Table>
<Caption>
                                                              PRINCIPAL AMOUNT
TITLE OF SERIES                                               (FILL IN AMOUNT)
- ---------------                                               ----------------
                                                           
7.75% Senior Notes due 2013.................................      $
</Table>

[ ] NOT TO TENDER ANY ORIGINAL NOTES HELD BY YOU FOR THE ACCOUNT OF THE
    UNDERSIGNED.

     IF NO BOX IS CHECKED, A SIGNED AND RETURNED INSTRUCTION TO BOOK-ENTRY
TRANSFER PARTICIPANT WILL BE DEEMED TO INSTRUCT YOU TO TENDER ALL ORIGINAL NOTES
HELD BY YOU FOR THE ACCOUNT OF THE UNDERSIGNED.

     If the undersigned instructs you to tender the Original 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 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 (i) any Exchange Notes
received are being acquired in the ordinary course of business of the
undersigned; (ii) the undersigned does not have an arrangement or understanding
with any person to participate in the distribution of the Original Notes or the
Exchange Notes within the meaning of the Securities Act; (iii) the undersigned
is not an "affiliate," as defined in Rule 405 under the Securities Act, of the
Company or, if it is such an affiliate, it will comply with the registration and
prospectus delivery requirements of the Securities Act to the extent applicable;
(iv) if the undersigned is not a broker-dealer, it is not engaged in, and does
not intend to engage in, a distribution of Exchange Notes and (v) if the
undersigned is a broker-dealer that will receive Exchange Notes for its own
account in exchange for Original Notes that were acquired as a result of market-
making activities or other trading activities, it will deliver a prospectus in
connection with any resale of such Exchange Notes; however, by so acknowledging
and by delivering a prospectus, the undersigned will not be deemed to admit that
it is an "underwriter" within the meaning of the Securities Act.

                                        3


                                   SIGN HERE

Name of beneficial owner(s):
- --------------------------------------------------------------------------------

Signature(s):
- --------------------------------------------------------------------------------

Name(s) (please print):
- --------------------------------------------------------------------------------

Address:
         -----------------------------------------------------------------------

Telephone Number:
- --------------------------------------------------------------------------------

Taxpayer Identification or Social Security Number:
- --------------------------------------------------------------------------------

Date:
- --------------------------------------------------------------------------------

                                        4