premium, if any, and interest (the “ Guarantees ”) by Tyco International Ltd., a Swiss company (the “ Guarantor ”), and will have the terms set forth in Schedule III hereto.  The Securities and the guarantees are to be issued pursuant to the indenture, dated as of January 9, 2009, as supplemented by the second supplemental indenture, to be dated as of October 5, 2009 (together, the “ Indenture ”), among the Company, the Guarantor and Deutsche Bank Trust Company Americas, as trustee (the “ Trustee ”).

The Company and the Guarantor have filed with the Securities and Exchange Commission (the “ Commission ”) a registration statement, including a prospectus (the file number of which is set forth on Schedule III hereto) on Form S-3, relating to securities (the “ Shelf Securities ”), including the Securities, to be issued from time to time by the Company and the Guarantor.  The registration statement as amended to the date of this agreement, including the information (if any) deemed to be part of the registration statement at the time of effectiveness pursuant to Rule 430A or Rule 430B under the Securities Act of 1933, as amended (the “ Securities Act ”), is hereinafter referred to as the “ Registration Statement ,” and the related prospectus covering the Shelf Securities dated May 1, 2009 in the form first used to confirm sales of the Securities (or in the form first made available to the Underwriters by the Company and the Guarantor to meet requests of purchasers pursuant to Rule 173 under the Securities Act) is hereinafter referred to as the “ Basic Prospectus .”  The Basic Prospectus, as supplemented by the prospectus supplement specifically relating to the Securities in the form first used to confirm sales of the Securities (or in the form first made available to the Underwriters by the Company and the Guarantor to meet requests of purchasers pursuant to Rule 173 under the Securities Act) is hereinafter referred to as the “ Prospectus ,” and the term “preliminary prospectus” means any preliminary form of the Prospectus.  For purposes of this Agreement, “free writing prospectus” has the meaning set forth in Rule 405 under the Securities Act, “ Time of Sale Prospectus ” means the preliminary prospectus together with the free writing prospectuses, if any, each identified in Schedule II hereto, and “ broadly available road show ” means a “ bona fide electronic road show ” as defined in Rule 433(h)(5) under the Securities Act that has been made available without restriction to any person.  As used herein, the terms “Registration Statement,” “Basic Prospectus,” “preliminary prospectus,” “Time of Sale Prospectus” and “Prospectus” shall include the documents, if any, incorporated by reference therein.  The terms “supplement,” “amendment,” and “amend” as used herein with respect to the Registration Statement, the Basic Prospectus, the Time of Sale Prospectus, any preliminary prospectus or any free writing prospectus shall include all documents subsequently filed by the Company or the Guarantor with the Commission pursuant to the Securities Exchange Act of 1934, as amended (the “ Exchange Act ”), that are deemed to be incorporated by reference therein.

1.  Representations and Warranties . The Company and the Guarantor, jointly and severally, represent and warrant to, and agree with, each of the Underwriters that:

(a)            The Registration Statement has become effective; no stop order suspending the effectiveness of the Registration Statement is in effect, and no proceedings for such purpose are pending before or, to the knowledge of the Company and the Guarantor, threatened by the Commission.  If the Registration Statement is an automatic shelf registration statement as defined in Rule 405 under the Securities Act, the Company and the Guarantor are well-known seasoned issuers (as defined in Rule 405 under the Securities Act) eligible to use the Registration Statement as an automatic shelf

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registration statement and neither the Company nor the Guarantor has received notice that the Commission objects to the use of the Registration Statement as an automatic shelf registration statement.

(b)            (i) Each document, if any, filed or to be filed pursuant to the Exchange Act and incorporated by reference in the Time of Sale Prospectus or the Prospectus complied, or will comply when so filed, in all material respects with the Exchange Act and the applicable rules and regulations of the Commission thereunder, (ii) each part of the Registration Statement, when such part became effective, did not contain, and each such part, as amended or supplemented, if applicable, will not contain any untrue statement of a material fact or omit to state a material fact required to be stated therein or necessary to make the statements therein not misleading, (iii) the Registration Statement as of the date hereof does not contain any untrue statement of a material fact or omit to state a material fact required to be stated therein or necessary to make the statements therein not misleading, (iv) the Registration Statement and the Prospectus comply, and as amended or supplemented, if applicable, will comply in all material respects with the Securities Act and the applicable rules and regulations of the Commission thereunder, (v) the Time of Sale Prospectus does not, and at the time of each sale of the Securities in connection with the offering when the Prospectus is not yet available to prospective purchasers and at the Time of Delivery (as defined in Section 4(a)), the Time of Sale Prospectus, as then amended or supplemented, if applicable, will not, contain any untrue statement of a material fact or omit to state a material fact necessary to make the statements therein, in the light of the circumstances under which they were made, not misleading, (vi)  each broadly available road show, if any, when considered together with the Time of Sale Prospectus, does not contain any untrue statement of a material fact or omit to state a material fact necessary to make the statements therein, in the light of the circumstances under which they were made, not misleading and (vii) the Prospectus does not contain and at the Time of Delivery, as amended or supplemented, if applicable, will not contain any untrue statement of a material fact or omit to state a material fact necessary to make the statements therein, in the light of the circumstances under which they were made, not misleading, except that the representations and warranties set forth in this paragraph do not apply to (A) statements or omissions in the Registration Statement, the Time of Sale Prospectus,  the Prospectus or the bona fide electronic road show identified as an issuer free writing prospectus in Schedule IV hereto based upon information relating to any Underwriter furnished to the Company or the Guarantor in writing by such Underwriter through the Representatives expressly for use therein or (B) that part of the Registration Statement that constitutes the Statement of Eligibility (Form T-1) under the Trust Indenture Act of 1939, as amended (the “ Trust Indenture Act ”), of the Trustee.

(c)            Neither the Company nor the Guarantor is an “ineligible issuer” in connection with the offering pursuant to Rules 164, 405 and 433 under the Securities Act.  Any issuer free writing prospectus (as defined in Rule 433(h) under the Securities Act) that the Company or the Guarantor is required to file pursuant to Rule 433(d) under the

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Securities Act has been, or will be, filed with the Commission in accordance with the requirements of the Securities Act and the applicable rules and regulations of the Commission thereunder.  Each issuer free writing prospectus that the Company or the Guarantor has filed, or is required to file, pursuant to Rule 433(d) under the Securities Act or that was prepared by or on behalf of or used or referred to by the Company or the Guarantor complies or will comply in all material respects with the requirements of the Securities Act and the applicable rules and regulations of the Commission thereunder.  Except for the issuer free writing prospectuses, if any, identified in Schedule II hereto and the electronic road show identified in Schedule IV hereto, if any, each furnished to you before first use, the Company and the Guarantor have not prepared, used or referred to, and will not, without your prior consent, prepare, use or refer to, any issuer free writing prospectus.

(d)            Each of the Company and the Guarantor has been duly formed and is validly existing as a company in good standing (to the extent good standing is applicable in such jurisdiction) under the laws of the jurisdiction of its formation, has the company power and authority to own its property and to conduct its business as described in the Time of Sale Prospectus and is duly qualified to transact business and is in good standing in each jurisdiction in which the conduct of its business or its ownership or leasing of property requires such qualification, except to the extent that the failure to be so qualified or be in good standing is not reasonably likely to result in a material adverse effect on the general affairs, management, consolidated financial condition, consolidated shareholders’ equity or consolidated results of operations of the Guarantor and its subsidiaries taken as a whole (a “ Material Adverse Effect ”).

(e)            Each of Tyco International Holding S.a.r.l., a Luxembourg limited liability company, and ADT Security Services, Inc., a Delaware corporation (the “ Significant Subsidiaries ”), has been duly formed, is validly existing as a corporation or company, as the case may be, in good standing under the laws of the jurisdiction of its incorporation or formation (to the extent good standing is applicable in such jurisdiction), has the corporate or company power and authority to own its property and to conduct its business as described in the Time of Sale Prospectus and is duly qualified to transact business and is in good standing in each jurisdiction in which the conduct of its business or its ownership or leasing of property requires such qualification (to the extent good standing is applicable in such jurisdiction), except to the extent that the failure to be so qualified or be in good standing is not reasonably likely to result in a Material Adverse Effect;  all of the outstanding shares of capital stock of the Company and each Significant Subsidiary have been duly and validly authorized and issued, are fully paid and non-assessable and are owned directly or indirectly by the Guarantor, free and clear of all liens, encumbrances, equities or claims.

(f)             This Agreement has been duly authorized, executed and delivered by each of the Company and the Guarantor.

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(g)            The Securities have been duly authorized by the Company.  When executed and authenticated in accordance with the provisions of the Indenture and delivered to and paid for by the Underwriters in accordance with the terms of this Agreement, the Securities will have been duly executed, authenticated, issued and delivered and will be valid and binding obligations of the Company, enforceable in accordance with their terms, subject to the effects of applicable bankruptcy, insolvency and similar laws affecting the enforcement of creditors’ rights generally and equitable principles of general applicability and the Securities will be entitled to the benefits of the Indenture.

(h)            The Guarantees have been duly authorized by the Guarantor.  When the Securities are executed and authenticated in accordance with the provisions of the Indenture and delivered to and paid for by the Underwriters in accordance with the terms of this Agreement, the Guarantees will be the valid and binding obligations of the Guarantor, enforceable in accordance with their terms, subject to the effects of applicable bankruptcy, insolvency and similar laws affecting the enforcement of creditors’ rights generally and equitable principles of general applicability.

(i)             The Indenture has been duly qualified under the Trust Indenture Act, duly authorized by each of the Company and the Guarantor and, when executed and delivered in accordance with the terms of this Agreement, will constitute a valid and legally binding instrument, enforceable against the Company and the Guarantor in accordance with its terms, subject to the effects of applicable bankruptcy, insolvency and similar laws affecting the enforcement of creditors’ rights generally and equitable principles of general applicability; and the Securities, the Guarantees and the Indenture will conform in all material respects to the descriptions thereof in the Time of Sale Prospectus and will be in substantially the form previously delivered to you.

(j)             The execution and delivery by the Company and the Guarantor of, and the performance by them of their obligations under, this Agreement, the Indenture, the Securities and the Guarantees will not contravene (i) any provision of applicable law or the charter or other governing documents or bye-laws of the Company or the Guarantor, (ii) any agreement or other instrument binding upon the Guarantor, the Company or any of the Significant Subsidiaries that is material to the Guarantor and its subsidiaries, taken as a whole, or (iii) any judgment, order or decree of any governmental body, agency or court having jurisdiction over the Guarantor, the Company or any Significant Subsidiary, and no consent, approval, authorization or order of, or qualification with, any governmental body or agency is required for the performance by the Company or the Guarantor of its obligations under this Agreement, the Indenture, the Securities or the Guarantees, except such as may be required by the securities or Blue Sky laws of the various states in connection with the offer and sale of the Securities and the Guarantees by the Underwriters.

(k)            Except as set forth in the Time of Sale Prospectus, there has not occurred any material adverse change, or any development that is reasonably likely to involve a prospective

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material adverse change, in the condition, financial or otherwise, or in the earnings, business or operations of the Guarantor and its subsidiaries, taken as a whole, since the date of the latest audited consolidated financial statements included in the Time of Sale Prospectus.

(l)             There are no legal or governmental proceedings pending or, to the knowledge of the Company or the Guarantor, threatened to which any of the Guarantor, the Company or the Significant Subsidiaries is a party other than proceedings accurately described in all material respects in the Time of Sale Prospectus and proceedings that, individually or in the aggregate, have had or are reasonably likely to result in a Material Adverse Effect.

(m)           Except as described in the Time of Sale Prospectus, no executive officer or director of the Company, Guarantor or any Significant Subsidiary is aware of or has taken any action, directly or indirectly, that would result in a material violation by such persons of the Foreign Corrupt Practices Act of 1977, as amended, and the rules and regulations thereunder (the “ FCPA ”), including, without limitation, making use of the mails or any means or instrumentality of interstate commerce corruptly in furtherance of an offer, payment, promise to pay or authorization of the payment of any money, or other property, gift, promise to give, or authorization of the giving of anything of value to any “foreign official” (as such term is defined in the FCPA) or any foreign political party or official thereof or any candidate for foreign political office, in contravention of the FCPA except for actions that, individually or in the aggregate, is not reasonably likely to result in a Material Adverse Effect.

(n)            The consolidated historical financial statements and schedules of the Guarantor and its consolidated subsidiaries incorporated by reference in the Time of Sale Prospectus present fairly the consolidated financial condition, results of operations and cash flows of the Guarantor and its subsidiaries as of the dates and for the periods indicated, comply as to form in all material respects with the applicable accounting requirements of Regulation S-X and have been prepared in conformity with U.S. generally accepted accounting principles applied on a consistent basis throughout the periods involved (except as otherwise noted therein) and the pro forma financial information included in the Time of Sale Prospectus, if any, has been prepared in conformity with generally accepted accounting principles applied on a consistent basis, the assumptions on which such pro forma financial information has been prepared are reasonable, and such pro forma financial information has been prepared in accordance with the applicable accounting requirements of the Securities Act and the rules and regulations of the Commission thereunder.

(o)            Neither the Company nor the Guarantor is, and after giving effect to the offering and sale of the Securities and the Guarantees and the application of the proceeds thereof as described in the Time of Sale Prospectus, neither will be, required to register as an “investment company” as such term is defined in the Investment Company Act of 1940, as amended (the “ Investment Company Act ”).

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(p)            Each preliminary prospectus with respect to the Securities filed as part of the registration statement as originally filed or as part of any amendment thereto, or filed pursuant to Rule 424 under the Securities Act, complied when so filed in all material respects with the Securities Act and the applicable rules and regulations of the Commission thereunder.

(q)            Prior to the date hereof, neither the Company, the Guarantor nor any of their affiliates has taken any action which is designed to or which has constituted or which might cause or result in stabilization or manipulation of the price of any security of the Company or the Guarantor in connection with the offering of the Securities.

(r)             Neither the Company nor the Guarantor is (i) in violation of the charter documents or other governing documents or bye-laws of the Company and the Guarantor, as applicable, (ii) in default in the performance or observance of any obligation, agreement, covenant or condition contained in any indenture, mortgage, deed of trust, loan agreement, lease or other agreement or instrument to which it is a party or by which it or any of its properties may be bound, which default has had or is reasonably likely to result in a Material Adverse Effect.

(s)            The statements set forth in the Basic Prospectus under the caption “Description of Debt Securities and Guarantee of Debt Securities” and in the Time of Sale Prospectus and the Prospectus under the caption “Description of the Notes and Guarantees”, insofar as they purport to describe the material terms of the Securities and the Guarantees, and the statements set forth in the Time of Sale Prospectus and the Prospectus under the caption “Underwriting”, insofar as they purport to describe the material provisions of the laws and documents referred to therein, fairly describe, in all material respects, those terms and provisions.

(t)             To the extent that the statements set forth in the Prospectus under the caption “Certain Luxembourg, U.S. Federal and Swiss Income Tax Considerations” purport to describe certain provisions of the tax laws referred to therein, such summaries fairly describe, in all material respects, such provisions.

(u)            Deloitte & Touche LLP, who have certified certain financial statements of the Guarantor, are an independent registered public accounting firm as required by the Securities Act and the rules and regulations of the Commission thereunder.

(v)            Except as disclosed in the Time of Sale Prospectus, since the date of the latest audited consolidated financial statements included in the Time of Sale Prospectus, there has been no change in internal control over the consolidated financial reporting of the Guarantor that has materially affected, or is reasonably likely to materially affect, the internal control over the consolidated financial reporting.

(w)           The Guarantor maintains a system of internal control over financial reporting (as such term is defined in Rule 13a-15(f) of the Exchange Act) that complies with the

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requirements of the Exchange Act and has been designed by the Guarantor’s principal executive officer and principal financial officer, or under their supervision, to provide reasonable assurance regarding the reliability of financial reporting and the preparation of financial statements for external purposes in accordance with generally accepted accounting principles.  Except as disclosed in the Time of Sale Prospectus, the internal control over consolidated financial reporting of the Guarantor is effective and the Guarantor is not aware of any material weaknesses in its internal control over financial reporting.

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

(y)            Except as is not reasonably likely to result in a Material Adverse Effect (i) neither the Company nor any of its subsidiaries nor, to the knowledge of the Company, any director, officer, agent, employee or affiliate of the Company or any of its subsidiaries is currently subject to any sanctions administered by the Office of Foreign Assets Control of the U.S. Treasury Department (“ OFAC ”), and (ii) to the best of the Company’s knowledge, the Company will not directly or indirectly use the proceeds of the offering, or lend, contribute or otherwise make available such proceeds to any subsidiary, joint venture partner or other person or entity, for the purpose of financing the activities of any person currently subject to any U.S. sanctions administered by OFAC.

(z)             The Company represents that the choice of law provisions set forth in this agreement are legal, valid and binding under the laws of Luxembourg, and will be recognized and given effect to by the courts of Luxembourg (unless a court determined that doing so would be contrary to public policy in Luxembourg); the Company has, under the laws of Luxembourg, the power to submit to the jurisdiction of New York courts; the irrevocable submission of the Company to the jurisdiction of the New York courts and the waiver by the Company of any immunity and any objection to the venue of the proceeding in a New York court, included in this agreement, are legal, valid and binding under the laws of Luxembourg; neither the Company nor any of its assets is entitled to immunity (or any similar defense) from suit, execution, attachment or other legal process in Luxembourg; this Agreement is in proper legal form under the laws of Luxembourg, for the enforcement thereof against the Company and nothing in Luxembourg law prevents suit upon this Agreement in the courts of Luxembourg; and it is not necessary (a) in order to enable the Underwriters to exercise or enforce their rights under this Agreement in Luxembourg or (b) by reason of the entry into and performance of this Agreement, that any of the Underwriters should be licensed, qualified, authorized or entitled to do business in Luxembourg.

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(aa)          The Guarantor represents that the choice of law provisions set forth in this agreement are legal, valid and binding under the laws of Switzerland, and will be recognized and given effect to by the courts of Switzerland (unless a Swiss court has determined that doing so would be contrary to public policy in Switzerland); the Guarantor can, under the laws of Switzerland, submit to the jurisdiction of New York courts; the irrevocable submission of the Guarantor to the jurisdiction of the New York courts and the waiver by the Guarantor of any immunity and any objection to the venue of the proceeding in a New York court, included in this agreement, are legal, valid and binding under the laws of Switzerland; neither the Guarantor nor any of its assets is entitled to immunity (or any similar defense) from suit, execution, attachment or other legal process in Switzerland; this Agreement is in proper legal form under the laws of Switzerland, for the enforcement thereof against the Guarantor and nothing in Swiss law prevents suit upon this Agreement in the courts of Switzerland; and it is not necessary (a) in order to enable the Underwriters to exercise or enforce their rights under this Agreement in Switzerland or (b) by reason of the entry into and performance of this Agreement, that any of the Underwriters should be licensed, qualified, authorized or entitled to do business in Switzerland.

2.        Agreements of the Company and the Underwriters to Sell and Purchase .  Upon the basis of the representations and warranties herein contained but subject to the conditions hereinafter stated, the Company hereby agrees to issue and sell to the several Underwriters, and each Underwriter agrees, severally and not jointly, to purchase from the Company the respective principal amount of Securities set forth in Schedule I hereto opposite its name at a purchase price of 99.178% of the principal amount thereof (the “ Purchase Price ”) in each case plus accrued interest, if any, to the Time of Delivery (as defined below).

3.        Terms of Offering . The Company is advised by you that the Underwriters propose to make a public offering of their respective portions of the Securities as soon after the Registration Statement and this Agreement have become effective as in your judgment is advisable.  The Company is further advised by you that the Securities are to be offered to the public upon the terms set forth in the Prospectus.

4.        Payment for and Delivery of the Securities .

(a)            Payment for the Securities shall be made by or on behalf of the Representatives to the Company in Federal (same-day) funds in New York City against delivery of such Securities for the respective accounts of the several Underwriters at 10:00 a.m., New York City time, on October 5, 2009 or such other time and date as the Representatives and the Company may agree upon in writing.  Such time and date are herein called the “ Time of Delivery ”.

(b)            The Securities to be purchased by each Underwriter hereunder will be represented by one or more definitive global Securities in book-entry form which will be deposited by or on behalf of the Company with The Depository Trust Company (“ DTC ”) or its designated custodian.  The Securities shall be delivered to the Representatives at the

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Time of Delivery for the respective accounts of the several Underwriters, with any transfer taxes payable in connection with the transfer of the Securities to the Underwriters duly paid by the Company, against payment therefor plus accrued interest, if any, to the date of payment and delivery.

5.        Conditions to the Underwriters’ Obligations .  The several obligations of the Underwriters to purchase and pay for the Securities at the Time of Delivery are subject, in their discretion, to the representations and warranties of the Company and Guarantor contained in this Agreement being true and correct as of the Time of Delivery, that the Company and the Guarantor shall have each performed all of their respective obligations hereunder theretofore to be performed, and further subject to the following conditions:

(a)            On or after 1:27 p.m. on September 30, 2009 (the “ Applicable Time ”), there shall not have occurred any downgrading, nor shall any notice have been given of any intended or potential downgrading or of any r