EXHIBIT 10.1

EXECUTION VERSION

$300,000,000

TransDigm Inc.

7¾% Senior Subordinated Notes due 2014

PURCHASE AGREEMENT

January 31, 2007

CREDIT SUISSE SECURITIES (USA) LLC (“ Credit Suisse ”)
LEHMAN BROTHERS INC. (“ Lehman ”)
  As representatives of the several initial purchasers

c/o Credit Suisse Securities (USA) LLC
Eleven Madison Avenue,
New York, N.Y. 10010-3629

and

c/o Lehman Brothers Inc.
745 Seventh Avenue
New York, N.Y. 10019

Dear Sirs:

1.  TransDigm Inc., a Delaware corporation (the “ Company ”), proposes, subject to the terms and conditions stated herein, to issue and sell to the several initial purchasers named in Schedule A hereto (collectively, the “ Purchasers ”) U.S.$300,000,000 principal amount of its 7¾% Senior Subordinated Notes due 2014 (the “ Offered Securities ”) to be issued as additional securities under the indenture dated as of June 23, 2006, among the Company, TransDigm Group Incorporated (“ TD Group ”), the subsidiary guarantors from time to time party thereto and The Bank of New York Trust Company, N.A., as trustee (the “ Trustee ”), as supplemented by the First Supplemental Indenture thereto, dated as of November 2, 2006 (as so supplemented, the “ Indenture ”).  The United States Securities Act of 1933, as amended, is herein referred to as the “ Securities Act .”

As described under the heading “The Transactions” in the Preliminary Offering Circular (as defined below) and the Final Offering Circular (as defined below), the Company intends to acquire (the “ Acquisition ”) all of the equity interests of Aviation Technologies, Inc., a Delaware corporation (“ ATI ”).

In order to consummate the Acquisition, the Company has organized Project Coffee Acquisition Co., a Delaware corporation and a wholly-owned subsidiary of the Company (“ Merger Sub ”).  Pursuant to the Agreement and Plan of Merger, dated as of January 9, 2007 (the “ Merger Agreement ”), among the Company, Merger Sub and ATI, Merger Sub will be merged with and into ATI, with ATI continuing as the surviving corporation and a wholly-owned subsidiary of the Company (the “ Merger ”).

In connection with the Acquisition, the Company will amend its existing credit agreement, dated as of June 23, 2006 (the “ Existing Credit Agreement ”), to, among other things, (i) provide for an increase in the revolving credit facility thereunder of $50,000,000, (ii) provide for an incremental term loan of $130,000,000 (the “ Incremental Term Loan ”) and (iii) make certain other amendments to the terms

thereof as described more fully in the Preliminary Offering Circular and the Final Offering Circular (as so amended, the “ Amended Credit Agreement ”).

The Acquisition, the issuance of the Offered Securities and the execution of (i) the Amended Credit Agreement, (ii) this Agreement, (iii) a supplemental indenture to the Indenture (the “ Supplemental Indenture ”), which Supplemental Indenture will cause the ATI Guarantors (as defined below) to guarantee the Offered Securities effective upon the consummation of the Merger, (iv) the Registration Rights Agreement (as defined below) and (v) counterparts to this Agreement and the Registration Rights Agreement by the ATI Guarantors upon consummation of the Merger and the consummation of all other related transactions contemplated by the Merger Agreement, this Agreement or described in the Preliminary Offering Circular and the Final Offering Circular under the headings “The Transactions” are referred to herein collectively as the “ Transactions ”.

The Offered Securities under the Indenture will be fully and unconditionally, and jointly and severally, guaranteed on a senior subordinated unsecured basis by (i) TD Group, (ii) each of the subsidiaries of the Company listed on Schedule B hereto (the “ Company Guarantors ”) and (iii) effective upon the consummation of the Merger, ATI and each of its subsidiaries listed on Schedule C hereto (ATI and the subsidiaries of ATI listed on Schedule C hereto are sometimes collectively referred to herein as the “ ATI Guarantors ”).  In connection therewith, and concurrently with the consummation of the Merger, each of the ATI Guarantors will each execute the Supplemental Indenture and counterparts to this Agreement and the Registration Rights Agreement.  The guarantees described in this paragraph are collectively referred to as the “ Guarantees ,” and TD Group, the Company Guarantors and the ATI Guarantors are collectively referred to as the “ Guarantors ”.

The holders of the Offered Securities will be entitled to the benefits of a Registration Rights Agreement to be entered into on the Closing Date (as defined below) among the Company, the Guarantors and Credit Suisse and Lehman, as representatives of the several Purchasers (the “ Registration Rights Agreement ”), pursuant to which, and subject to the terms and conditions set forth therein, the Company shall agree to file a registration statement with the Securities and Exchange Commission (the “ Commission ”) registering the resale of the Offered Securities under the Securities Act; provided , however , that the undertakings of the ATI Guarantors as set forth in the Registration Rights Agreement will not become effective until such Guarantors execute their respective counterparts to the Registration Rights Agreement.

This Agreement (including the counterparts to be executed concurrently with the consummation of the Merger by the ATI Guarantors), the Indenture, the Supplemental Indenture (to be executed concurrently with the consummation of the Merger by the ATI Guarantors), the Offered Securities and the Registration Rights Agreement (including the counterparts to be executed concurrently with the consummation of the Merger by the ATI Guarantors) are referred to in this Agreement collectively as the “ Operative Documents .”  The Merger Agreement, the Amended Credit Agreement and the Operative Documents are referred to in this Agreement collectively as the “ Transaction Documents ”.

References in this Agreement to the subsidiaries of the Company or any Guarantor shall include all direct and indirect subsidiaries of the Company or such Guarantor, both on the date of this Agreement and after the consummation of the Merger, and the representations and warranties in this Agreement with respect to the Company or any Guarantor and their respective subsidiaries shall be deemed to be representations and warranties with respect to the Company and the Guarantors and their respective subsidiaries both prior to and after the consummation of the Merger.

The Company and the Guarantors hereby agree with the Purchasers as follows:

2.  Representations and Warranties of the Company and the Guarantors.   The Company and the Guarantors, jointly and severally, represent and warrant to, and agree with, the Purchasers that:

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(a)  A preliminary offering circular (the “ Preliminary Offering Circular ”) relating to the Offered Securities to be offered by the Purchasers and a final offering circular (the “ Final Offering Circular ”)disclosing the offering price and other final terms of the Offered Securities and dated as of the date of this Agreement (even if finalized and issued subsequent to the date of this Agreement) have been or will be prepared by the Company.  “ General Disclosure Package ” means the Preliminary Offering Circular, together with any Issuer Free Writing Communication (as hereinafter defined) existing at the Applicable Time (as hereinafter defined), including the Confidential Offering Circular Supplement, dated January 30, 2007 (the “ Supplement ”), and the information which is intended for general distribution to prospective investors, as evidenced by its being specified in Schedule D  to this Agreement (including the term sheet listing the final terms of the Offered Securities and their offering, included in Schedule E to this Agreement, which is referred to as the “ Terms Communication ”).  “ Applicable Time ” means 10:55 a.m. (New York City time) on the date of this Agreement.  As of the date of this Agreement, the Final Offering Circular does not and, as of the Closing Date, the Final Offering Circular will not include any untrue statement of a material fact or omit to state any material fact necessary in order to make the statements therein, in the light of the circumstances under which they were made, not misleading.  At the Applicable Time, neither (i) the General Disclosure Package, nor (ii) any individual Supplemental Marketing Material (as hereinafter defined), when considered together with the General Disclosure Package, included, or will as of the Closing Date include, any untrue statement of a material fact or omitted, or will as of the Closing Date omit, to state any material fact necessary in order to make the statements therein, in the light of the circumstances under which they were made, not misleading.  The preceding two sentences do not apply to statements in or omissions from the Preliminary Offering Circular, the Final Offering Circular, the General Disclosure Package or any Supplemental Marketing Material based upon written information furnished to the Company by any Purchaser through Credit Suisse specifically for use therein, it being understood and agreed that the only such information is that described as such in Section 8(b) hereof.

“ Free Writing Communication ” means a written communication (as such term is defined in Rule 405 under the Securities Act) that constitutes an offer to sell or a solicitation of an offer to buy the Offered Securities and is made by means other than the Preliminary Offering Circular or the Final Offering Circular.  “ Issuer Free Writing Communication ” means a Free Writing Communication prepared by or on behalf of the Company, used or referred to by the Company or containing a description of the final terms of the Offered Securities or of their offering, in the form retained in the Company’s records.  “ Supplemental Marketing Material ” means any Issuer Free Writing Communication other than any Issuer Free Writing Communication specified in Schedule D to this Agreement.

(b)  Each of the Company and TD Group has been duly incorporated and is an existing corporation in good standing under the laws of the State of Delaware, with power and authority (corporate and other) to own its properties and conduct its business as described in the General Disclosure Package; and the Company is duly qualified to do business as a foreign corporation in good standing in all other jurisdictions in which its ownership or lease of property or the conduct of its business requires such qualification, except where the failure to be so qualified or in good standing would not, individually or in the aggregate, reasonably be expected to have a material adverse effect on the condition (financial or otherwise), business, properties or results of operations of TD Group and its subsidiaries, taken as a whole (“ Material Adverse Effect ”).

(c)  Each subsidiary of the Company has been duly incorporated and is an existing corporation in good standing under the laws of the jurisdiction of its incorporation, with power and authority (corporate and other) to own its properties and conduct its business as described in the General Disclosure Package; and each subsidiary of the Company is duly qualified to do business as a foreign corporation in good standing in all other jurisdictions in which its ownership or lease of property or the conduct of its business requires such qualification, except where the

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failure to be so qualified or in good standing would not, individually or in the aggregate, reasonably be expected to have a Material Adverse Effect; all of the issued and outstanding capital stock of each subsidiary of the Company has been duly authorized and validly issued and is fully paid and nonassessable; and the capital stock of each subsidiary owned by the Company, directly or through subsidiaries, is owned free from liens, encumbrances and defects, except for liens, encumbrances or defects on the capital stock of the subsidiaries (direct and indirect) of the Company granted in favor of the lenders under or related to the Amended Credit Agreement; provided, however, that the foregoing representations and warranties as to the liens, encumbrances and defects on the capital stock of the subsidiaries of the Company shall only be made with respect to the ATI Guarantors on the Closing Date after giving effect to the repayment of ATI’s existing indebtedness as further described in the General Disclosure Package.

(d)  The Indenture has been duly authorized, executed and delivered by the Company, TD Group and the Company Guarantors; the Offered Securities have been duly authorized by the Company, and when the Offered Securities are delivered and paid for pursuant to this letter agreement (this “ Agreement ”) on the Closing Date (as defined below), such Offered Securities will have been duly executed, authenticated, issued and delivered, will be consistent in all material respects with the information in the General Disclosure Package and will conform in all material respects to the description thereof contained in the Final Offering Circular,and the Indenture and such Offered Securities will constitute valid and legally binding obligations of the Company, enforceable in accordance with their terms, except that the enforcement thereof may be limited by (i) bankruptcy, insolvency, fraudulent transfer, reorganization, moratorium and similar laws of general applicability relating to or affecting creditors’ rights and (ii) general equity principles and the discretion of the court before which any proceeding therefor may be brought, whether at law or in equity.

(e)  Upon the consummation of the Merger, the Supplemental Indenture and the Guarantee of the Offered Securities by the ATI Guarantors will be duly authorized, executed and delivered by each of the ATI Guarantors and will be consistent in all material respects with the information in the General Disclosure Package and will conform to the description thereof contained in the Final Offering Circular. When the Offered Securities and the Guarantees have been issued, executed and authenticated in accordance with the terms of this Agreement, the Indenture and the Supplemental Indenture, each Guarantee of each ATI Guarantor with respect to such Offered Securities will constitute a valid and legally binding obligation of such ATI Guarantor, enforceable in accordance with its terms, except that the enforcement thereof may be limited by (i) bankruptcy, insolvency, fraudulent transfer, reorganization, moratorium and similar laws of general applicability relating to or affecting creditors’ rights and (ii) general equity principles and the discretion of the court before which any proceeding therefor may be brought, whether at law or in equity.

(f)  On the Closing Date, the Indenture, as supplemented by the Supplemental Indenture, will conform in all material respects to the requirements of the United States Trust Indenture Act of 1939, as amended (the “ Trust Indenture Act ”), and the rules and regulations of the Commission applicable to an indenture which is qualified thereunder.

(g)  The Exchange Securities (as defined in the Registration Rights Agreement) have been, or as of the Registered Exchange Offer (as defined in the Registration Rights Agreement) will be, duly and validly authorized by the Company and, when duly executed by the Company in accordance with the terms of the Indenture upon exchange for the Initial Securities (as defined in the Registration Rights Agreement), will be validly issued and delivered, and will constitute valid and binding obligations of the Company entitled to the benefits of the Indenture, enforceable in accordance with their terms, except that the enforcement thereof may be limited by (1) bankruptcy, insolvency, fraudulent transfer, reorganization, moratorium and similar laws of general applicability relating to or affecting creditors’ rights and (2) general equity principles and

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the discretion of the court before which any proceeding therefor may be brought, whether at law or in equity.

(h)  The Guarantee of the Exchange Securities by each of the Guarantors (each, an “ Exchange Security Guarantee ” and together, the “ Exchange Security Guarantees ”) will be, as of the Closing Date or as of the Registered Exchange Offer, duly authorized by each of the Guarantors.  When the Exchange Security Guarantees have been issued, executed and authenticated in accordance with the terms of the Registered Exchange Offer, the Indenture and the Supplemental Indenture, the Exchange Security Guarantee of each Guarantor will constitute a valid and legally binding obligation of such Guarantor, enforceable in accordance with its terms, except that the enforcement thereof may be limited by (i) bankruptcy, insolvency, fraudulent transfer, reorganization, moratorium and similar laws of general applicability relating to or affecting creditors’ rights and (ii) general equity principles and the discretion of the court before which any proceeding therefor may be brought, whether at law or in equity.

(i)  Except as disclosed in the General Disclosure Package, there are no contracts, agreements or understandings between the Company or the Guarantors, on the one hand, and any person, on the other hand, that would give rise to a valid claim against the Company, any Guarantor  or any Purchaser for a brokerage commission, finder’s fee or other like payment in connection with the transactions contemplated by this Agreement.

(j)  No consent, approval, authorization, or order of, or filing with, any governmental agency or body or any court is required for (i) the consummation by the Company or the Guarantors of the transactions contemplated by this Agreement or the Registration Rights Agreement in connection with the issuance and sale of the Offered Securities or the Exchange Securities by the Company and the issuance of the Guarantees or the Exchange Security Guarantees by the Guarantors or (ii) the consummation of the other transactions contemplated by the Transaction Documents, in any such case except for (A) the filing with the Secretary of State of the State of Delaware of the merger certificate effectuating the Merger, (B) as have been obtained or will be obtained prior to the Closing Date, (C) as may be required under state securities or “Blue Sky” laws in connection with the purchase and distribution of the Offered Securities by the Purchasers, (D) the order of the Commission declaring effective the Exchange Offer Registration Statement or, if required, the Shelf Registration Statement (each as defined in the Registration Rights Agreement) and (E) in the case of clause (ii) immediately above only, as set forth on Schedule 4.2(b) of the Merger Agreement (the failure of which to obtain would not, individually or in the aggregate, reasonably be expected to have a Material Adverse Effect).

(k)  The execution, delivery and performance by each of the Company and the Guarantors of the Transaction Documents will not result in a breach or violation of any of the terms and provisions of, or constitute a default under, (i) any statute or any rule, regulation or order of any governmental agency or body or any court, domestic or foreign, having jurisdiction over those parties or any of their properties, (ii) assuming that the Amended Credit Agreement has become effective, any agreement or instrument to which any of those parties is a party or by which any of those parties is bound or to which any of the properties of those parties is subject, or (iii) the charter or by-laws of any of those parties, except in the case of clauses (i) and (ii) above, for breaches, violations and defaults that would not, individually or in the aggregate, reasonably be expected to have a Material Adverse Effect.  The Company has full power and authority to authorize, issue and sell the Offered Securities as contemplated by this Agreement and the Guarantors have full power and authority to authorize and issue their respective Guarantees as contemplated by this Agreement.

(l)  This Agreement has been duly authorized, executed and delivered by the Company and the Company Guarantors; and on the Closing Date the counterpart to this Agreement will be duly authorized, executed and delivered by the ATI Guarantors.

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(m)  The Registration Rights Agreement has been duly authorized by the Company and the Company Guarantors and on the Closing Date will be duly authorized by the ATI Guarantors; on the Closing Date, the Registration Rights Agreement will be duly executed and delivered by the Company and the Guarantors and will be enforceable against the Company and the Guarantors in accordance with its terms, except that (i) the enforcement thereof may be limited by (A) bankruptcy, insolvency, fraudulent transfer, reorganization, moratorium and similar laws of general applicability relating to or affecting creditors’ rights and (B) general equity principles and the discretion of the court before which any proceeding therefor may be brought, whether at law or in equity and (ii) any rights to indemnity or contribution thereunder may be limited by federal and state securities laws and public policy considerations.

(n)  Except as disclosed in the General Disclosure Package, the Company, TD Group and their subsidiaries have good and marketable title to all material real properties and all other material properties and material assets owned by them, in each case, and except as disclosed in the General Disclosure Package, free from liens, encumbrances and defects that would materially affect the value thereof or materially interfere with the use made or to be made thereof by them; provided, however, that the foregoing representations and warranties shall only be made with respect to the ATI Guarantors on the Closing Date after giving effect to the repayment of ATI’s existing indebtedness as further described in the General Disclosure Package and except as disclosed in the General Disclosure Package, the Company, TD Group and their subsidiaries hold any material leased real or personal property under valid and enforceable leases with no exceptions that would materially interfere with the use made or to be made thereof by them.

(o)  The Company, TD Group and their subsidiaries possess adequate certificates, authorities or permits issued by appropriate governmental agencies or bodies necessary to conduct the business now operated by them and have not received any written notice of proceedings relating to the revocation or modification of any such certificate, authority or permit that, if determined adversely to the Company, TD Group or any of their subsidiaries, would, individually or in the aggregate, reasonably be expected to have a Material Adverse Effect.

(p)  No labor dispute with the employees of the Company, TD Group or any subsidiary thereof exists or, to the knowledge of the Company, is imminent that would, individually or in the aggregate, reasonably be expected to have a Material Adverse Effect.

(q)  The Company, TD Group and their subsidiaries own, possess (including by license or other agreement) or can acquire on reasonable terms, adequate trademarks, trade names and other rights to inventions, know-how, patents, copyrights, confidential information and other intellectual property (collectively, “ Intellectual Property Rights ”) necessary to conduct the business now operated by them, or presently employed by them, and have not received any written notice of infringement of or conflict with asserted rights of others with respect to any Intellectual Property Rights that, if determined adversely to the Company, TD Group or any of their subsidiaries, would individually or in the aggregate, reasonably be expected to have a Material Adverse Effect.

(r)  Except as disclosed in the General Disclosure Package, neither the Company, TD Group nor any of their subsidiaries (i) is in violation of any statute, rule, regulation, decision or order of any governmental agency or body or any court, domestic or foreign, relating to the use, disposal or release of hazardous or toxic substances or relating to the protection or restoration of the environment or human exposure to hazardous or toxic substances (collectively, “ Environmental Laws ”), (ii) owns or operates any real property contaminated with any substance that is subject to any Environmental Laws, (iii) is liable for any off-site disposal or contamination pursuant to any Environmental Laws, or (iv) is subject to any claim relating to any Environmental Laws, which violation, contamination, liability or claim would, individually or in the aggregate, reasonably be expected to have a Material Adverse Effect; and to the Company’s knowledge, there are no pending investigations which could reasonably be expected to lead to such a claim.

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(s)  Except as disclosed in the General Disclosure Package, there are no pending actions, suits or proceedings against or affecting the Company, TD Group, any of their subsidiaries or any of their respective properties that would, individually or in the aggregate, reasonably be expected to have a Material Adverse Effect, or would materially and adversely affect the ability of the Company or any of the Guarantors to perform their respective obligations under the Operative Documents, or which are otherwise material in the context of the sale of the Offered Securities; to the Company’s knowledge, no such actions, suits or proceedings are threatened against the Company, TD Group, any of their respective subsidiaries or any of their respective properties.

(t)  The financial statements included in the General Disclosure Package and the Final Offering Circular present fairly in all material respects the financial position of (1) TD Group (or, if applicable, TransDigm Holding Company) and its consolidated subsidiaries and (2) ATI and its consolidated subsidiaries, in each case as of the dates shown and their results of operations and cash flows for the periods shown, and, except as otherwise disclosed in the General Disclosure Package and the Final Offering Circular, such financial statements have been prepared in conformity with generally accepted accounting principles in the United States (“ GAAP ”) applied on a consistent basis, and the assumptions used in preparing the pro forma financial statements included in the General Disclosure Packageand the Final Offering Circular provide a reasonable basis for presenting the significant effects directly attributable to the transactions or events described therein, the related pro forma adjustments give appropriate effect to those assumptions, and the pro forma columns therein reflect the proper application of those adjustments to the corresponding historical financial statement amounts.

(u)  Except as disclosed in the General Disclosure Package, since the date of the latest audited financial statements of TD Group included in the General Disclosure Package there has been no material adverse change, nor any development or event involving a prospective material adverse change, in the condition (financial or other), business, properties or results of operations of TD Group and its subsidiaries taken as a whole, and, except as disclosed in or contemplated by the General Disclosure Package, there has been no dividend or distribution of any kind declared, paid or made by TD Group on any class of its capital stock.

(v)  TD Group is subject to the reporting requirements of either Section 13 or Section 15(d) of the Securities Exchange Act of 1934, as amended (the “ Exchange Act ”), and files reports with the Commission on the Electronic Data Gathering, Analysis, and Retrieval (EDGAR) system.

(w)  Neither the Company, TD Group nor any Guarantor is, and after giving effect to the Transactions none of them will be, an open-end investment company, unit investment trust or face-amount certificate company that is or is required to be registered under Section 8 of the United States Investment Company Act of 1940, as amended (the “ Investment Company Act ”); and neither the Company, TD Group nor any Guarantor is, and after giving effect to the Transactions, none of them will be, an “investment company” as defined in the Investment Company Act.

(x)  TD Group maintains disclosure controls and procedures (as such term is defined in Rule 13a-15(e) under the Exchange Act) that comply in all material respects with the requirements of the Exchange Act; such disclosure controls and procedures have been designed to ensure that material information relating to TD Group and its subsidiaries is made known to TD Group’s principal executive officer and principal financial officer by others within those entities.

(y)  No securities of the same class (within the meaning of Rule 144A(d)(3) under the Securities Act) as the Offered Securities are listed on any national securities exchange registered under Section 6 of the Exchange Act or quoted in a U.S. automated inter-dealer quotation system.

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