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                                                                     EXHIBIT 4.3

                                EXCHANGE SECURITY

CUSIP No. 538021AM8

                THIS SECURITY IS A GLOBAL SECURITY WITHIN THE MEANING OF THE
INDENTURE HEREINAFTER REFERRED TO AND IS REGISTERED IN THE NAME OF A DEPOSITARY
OR A NOMINEE THEREOF. THIS SECURITY MAY NOT BE EXCHANGED IN WHOLE OR IN PART FOR
A SECURITY REGISTERED, AND NO TRANSFER OF THIS SECURITY IN WHOLE OR IN PART MAY
BE REGISTERED, IN THE NAME OF ANY PERSON OTHER THAN SUCH DEPOSITARY OR A NOMINEE
THEREOF, EXCEPT IN THE LIMITED CIRCUMSTANCES DESCRIBED HEREIN OR IN THE
INDENTURE.

                UNLESS THIS CERTIFICATE IS PRESENTED BY AN AUTHORIZED
REPRESENTATIVE OF THE DEPOSITORY TRUST COMPANY, A NEW YORK CORPORATION ("DTC"),
TO LITTON INDUSTRIES, INC. OR ITS AGENT FOR REGISTRATION OF TRANSFER, EXCHANGE,
OR PAYMENT, AND ANY CERTIFICATE ISSUED IS REGISTERED IN THE NAME OF CEDE & CO.
OR IN SUCH OTHER NAME AS IS REQUESTED BY AN AUTHORIZED REPRESENTATIVE OF DTC
(AND ANY PAYMENT IS MADE TO CEDE & CO. OR TO SUCH OTHER ENTITY AS IS REQUESTED
BY AN AUTHORIZED REPRESENTATIVE OF DTC), ANY TRANSFER, PLEDGE, OR OTHER USE
HEREOF FOR VALUE OR OTHERWISE BY OR TO ANY PERSON IS WRONGFUL INASMUCH AS THE
REGISTERED OWNER HEREOF, CEDE & CO., HAS AN INTEREST HEREIN.

                             LITTON INDUSTRIES, INC.

                            8% Senior Notes due 2009

No. R-1                                                        $400,000,000

                LITTON INDUSTRIES, INC., a corporation duly organized and
existing under the laws of the State of Delaware (herein called the "Company",
which term includes any successor Person under the Indenture hereinafter
referred to), for value received, hereby promises to pay to CEDE & CO., or
registered assigns, the principal sum of Four Hundred Million Dollars on October
15, 2009, and to pay interest thereon from October 18, 1999 or from the most
recent Interest Payment Date to which interest has been paid or duly provided
for, semi-annually on April 15 and October 15 in each year, commencing April 15,
2000, at the rate of 8% per annum, until the principal hereof is paid or made
available for payment. The interest so payable, and punctually paid or duly
provided for, on any Interest



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Payment Date will, as provided in such Indenture, be paid to the Person in whose
name this Security (or one or more Predecessor Securities) is registered at the
close of business on the Regular Record Date for such interest, which shall be
the April 1 or October 1 (whether or not a Business Day), as the case may be,
next preceding such Interest Payment Date. Any such interest not so punctually
paid or duly provided for will forthwith cease to be payable to the Holder on
such Regular Record Date and may either be paid to the Person in whose name this
Security (or one or more Predecessor Securities) is registered at the close of
business on a Special Record Date for the payment of such Defaulted Interest to
be fixed by the Trustee, notice whereof shall be mailed to Holders of Securities
of this series not less than 10 days prior to such Special Record Date, or be
paid at any time in any other lawful manner not inconsistent with the
requirements of any securities exchange on which the Securities of this series
may be listed, and upon such notice as may be required by such exchange, all as
more fully provided in said Indenture. Interest on the Securities of each series
shall be computed on the basis of a 360-day year of twelve 30-day months.

                Payment of the principal of (and premium, if any) and any such
interest on this Security will be made at the office or agency of the Company
maintained for that purpose in The Borough of Manhattan, The City of New York,
in such coin or currency of the United States of America as at the time of
payment is legal tender for payment of public and private debts; provided,
however, that at the option of the Company payment of interest may be made by
check mailed to the address of the Person entitled thereto as such address shall
appear in the Security Register.

                Reference is hereby made to the further provisions of this
Security set forth on the reverse hereof, which further provisions shall for all
purposes have the same effect as if set forth at this place.

                Unless the certificate of authentication hereon has been
executed by the Trustee referred to on the reverse hereof by manual signature,
this Security shall not be entitled to any benefit under the Indenture or be
valid or obligatory for any purpose.



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                IN WITNESS WHEREOF, the Company has caused this instrument to be
duly executed.




                                        LITTON INDUSTRIES, INC.


                                        By   Timothy G. Paulson
                                             Vice President and Treasurer


Attest:

Lynne M.O. Brickner
Secretary




CERTIFICATE OF AUTHENTICATION

This is one of the Securities of the series designated therein referred to in
the within-mentioned Indenture.

Dated:

                                        THE BANK OF NEW YORK,
                                                 As Trustee


                                        By   JoAnn Manieri
                                             Authorized Signatory



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                              [REVERSE OF SECURITY]

                This Security is one of a duly authorized issue of securities of
the Company (herein called the "Securities"), issued and to be issued in one or
more series under an Indenture, dated as of April 13, 1998 (herein called the
"Indenture", which term shall have the meaning assigned to it in such
instrument), between the Company and The Bank of New York, as Trustee (herein
called the "Trustee", which term includes any successor trustee under the
Indenture), and reference is hereby made to the Indenture for a statement of the
respective rights, limitations of rights, duties and immunities thereunder of
the Company, the Trustee and the Holders of the Securities and of the terms upon
which the Securities are, and are to be, authenticated and delivered. This
Security is one of the series designated on the face hereof, initially limited
in aggregate principal amount to $400,000,000, subject to certain exceptions
referred to in the Indenture. In addition, the Company may from time to time
without the consent of the Holders of Securities create and issue further
securities having the same terms and conditions as the Securities in all
respects (or in all respects except for the issue date and issue price) and so
that such further issue shall be consolidated and form a single series with the
outstanding securities of this series (including the Securities) or upon such
terms as the Company may determine at the time of their issue. References herein
to the Securities include (unless the context requires otherwise) any other
securities issued as described in this paragraph and forming a single series
with the Securities.

                The Securities of this series are subject to redemption upon not
less than 30 days' notice by mail, in whole or in part, at the option of the
Company at any time at a Redemption Price equal to the greater of (i) 100% of
the principal amount of the Securities so redeemed or (ii) as determined by a
Quotation Agent, the sum of the present values of the remaining scheduled
payments of principal and interest thereon (not including any portion of such
payments of interest accrued as of the date of redemption) discounted to the
redemption date on a semiannual basis (assuming a 360-day year consisting of
twelve 30-day months) at the Adjusted Treasury Rate, plus 15 basis points plus,
in each case, accrued interest thereon to the Redemption Date.

                  "Adjusted Treasury Rate" means, with respect to any Redemption
Date, the rate per annum equal to the



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semiannual equivalent yield to maturity of the Comparable Treasury Issue,
assuming a price for the Comparable Treasury Issue (expressed as a percentage of
its principal amount) equal to the Comparable Treasury Price for such Redemption
Date.

                "Comparable Treasury Issue" means the United States Treasury
security selected by a Quotation Agent as having a maturity comparable to the
remaining term of the Securities to be redeemed that would be utilized, at the
time of selection and in accordance with customary financial practice, in
pricing new issues of corporate debt securities of comparable maturity to the
remaining term of such Securities.

                "Comparable Treasury Issue" means, with respect to any
redemption date, (i) the average of the Reference Treasury Dealer Quotations for
that redemption date, after excluding the highest and lowest of the Reference
Treasury Dealer Quotations, or (ii) if the Trustee obtains fewer than three such
Reference Treasury Dealer Quotations, the average of all Reference Treasury
Dealer Quotations so received.

                "Quotation Agent" means the Reference Treasury Dealer appointed
by the Company.

                "Reference Treasury Dealer" means (i) each of J.P. Morgan
Securities Inc., Credit Suisse First Boston Corporation, Banc of America
Securities LLC, BNY Capital Markets, Inc., Chase Securities Inc. and Salomon
Smith Barney Inc. and their respective successors unless any of them ceases to
be a primary U.S. Government securities dealer in New York City (a "Primary
Treasury Dealer"), in which case the Company shall substitute another Primary
Treasury Dealer, and (ii) any other Primary Treasury dealer selected by the
Company.

                "Reference Treasury Dealer Quotations" means, with respect to
each Reference Treasury Dealer and any redemption date, the average, as
determined by the Company, of the bid and asked prices for Comparable Treasury
Issue (expressed in each case as a percentage of its principal amount) quoted in
writing to the Trustee by that Reference Treasury dealer at 5:00 p.m., New York
City time, on the third business day preceding that redemption date.

                  In the event of redemption of this Security in part only, a
new Security or Securities of this series and of like tenor for the unredeemed
portion hereof will be



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issued in the name of the Holder hereof upon the cancellation hereof.

                This Security shall have the benefit of the covenants and
agreements set forth herein and in the Indenture, subject to the limited
exceptions referred to in the Officers' Certificate of the Company creating the
Securities of this series (the "Officers' Certificate"). The Company shall not,
and shall not permit any Subsidiary (as defined below) to, create, assume or
suffer to exist any mortgage, pledge, lien, encumbrance, charge or security
interest (collectively, a "Lien") upon Restricted Property (as defined below) to
secure any debt of the Company, any Subsidiary or any other Person (as defined
below), without making effective provision whereby the Notes then outstanding
shall be secured by the Lien equally and ratably with such debt for so long as
such debt shall be so secured, except that the foregoing shall not prevent the
Company or any Subsidiary from creating, assuming or suffering to exist Liens of
the following character: (1) any Lien existing on the date of issuance of the
Notes; (2) any Lien existing on property owned or leased by a corporation at the
time it becomes a Subsidiary; (3) any Lien existing on property at the time of
the acquisition thereof by the Company or a Subsidiary; (4) any Lien to secure
any debt incurred prior to, at the time of, or within 12 months after the
acquisition of Restricted Property for the purpose of financing all or any part
of the purchase price thereof and any Lien to the extent that it secures debt
which is in excess of such purchase price and for the payment of which recourse
may be had only against such Restricted Property; (5) any Lien to secure any
debt incurred prior to, at the time of, or within 12 months after the completion
of the construction or commencement of commercial operation, alteration, repair
or improvement of Restricted Property for the purpose of financing all or any
part of the cost thereof and any Lien to the extent that it secures debt which
is in excess of such cost and for the payment of which recourse may be had only
against such Restricted Property; (6) any Lien securing debt of a Subsidiary
owing to the Company or to another Subsidiary; (7) any Lien in favor of the
United States of America or any State thereof or any other country, or any
agency, instrumentality or political subdivision of any of the foregoing, to
secure partial, progress, advance or other payments or performance pursuant to
the provisions of any contract or statute, or any Liens securing industrial
development, pollution control, or similar revenue bonds; (8) any extension,
renewal or replacement (or successive



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extensions, renewals or replacements) in whole or in part of any Lien referred
to in clauses (1) through (7) above, so long as the principal amount of debt so
secured at the time of the extension, renewal or replacement (except that, where
an additional principal amount of debt is incurred to provide funds for the
completion of a specific project, the additional principal amount, and any
related financing costs, may be secured by the Lien as well) and the Lien is
limited to the same property subject to the Lien so extended, renewed or
replaced (plus improvements on the property); and (9) any Lien not permitted by
clauses (1) through (8) above securing debt which, together with the aggregate
outstanding principal amount of all other debt of the Company and its
Subsidiaries owning Restricted Property which would otherwise be subject to the
foregoing restrictions and the aggregate Value (as defined below) of existing
Sale and Leaseback Transactions (as defined below) which would be subject to the
restrictions herein but for this clause (9), does not at any time exceed 15% of
Consolidated Net Tangible Assets (as defined below).

                The Company shall not enter into any Sale and Leaseback
Transaction, nor permit any Subsidiary owning Restricted Property so to do,
unless either (1) the Company or such Subsidiary would be entitled to incur
debt, in a principal amount at least equal to the Value of such Sale and
Leaseback Transaction, which is secured by Liens on the property to be leased
(without equally and ratably securing the outstanding Securities) because such
Liens would be of such character that no violation of any of the provisions
herein would result or (2) the Company during the six months immediately
following the effective date of such Sale and Leaseback Transaction causes to be
applied to (A) the acquisition of Restricted Property or (B) the voluntary
retirement of Funded Debt (as defined below) (whether by redemption, defeasance,
repurchase or otherwise) an amount equal to the Value of such Sale and Leaseback
Transaction.

                "Consolidated Net Tangible Assets" means the total amount of
assets (less applicable reserves and other properly deductible items) after
deducting (1) all current liabilities (excluding the amount of those which are
by their terms extendable or renewable at the option of the obligor to a date
more than 12 months after the date as of which the amount is being determined)
and (2) all goodwill, tradenames, trademarks, patents, unamortized debt discount
and expense and other like intangible assets, all as set forth on the most
recent balance sheet of the Company and



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its consolidated subsidiaries and determined in accordance with generally
accepted accounting principals.

                "Funded Debt" means indebtedness of the Company or a Subsidiary
owning Restricted Property maturing by its terms more than one year after its
creation and indebtedness classified as long-term debt under generally accepted
accounting principles and in each case ranking at least pari passu with the
Securities.

                "Restricted Property" means (1) any manufacturing facility, or
portion thereof, owned or leased by the Company or any Subsidiary and located
within the continental United States of America, which, in the opinion of the
Board of Directors, is of material importance to the business of the Company and
its Subsidiaries taken as a whole, but no such manufacturing facility, or
portion thereof, shall be deemed of material importance if its gross book value
(before deducting accumulated depreciation) is less than 2% of Consolidated Net
Tangible Assets, or (2) any shares of capital stock or indebtedness of any
Subsidiary owning any such manufacturing facility. As used in this definition,
"manufacturing facility" means property, plant and equipment used for actual
manufacturing such as quality assurance, engineering, maintenances, staging
areas for work in process materials, employees' eating and comfort facilities
and manufacturing administration, and it excludes sales offices, research
facilities and facilities used only for warehousing or general administration.

                "Sale and Leaseback Transaction" means any arrangement with any
individual, corporation, partnership, joint venture, association, joint-stock
company, trust, unincorporated organization or government or any agency or
political subdivision thereof ("Person") pursuant to which the Company or any
Subsidiary leases any Restricted Property that has been or is to be sold or
transferred by the Company or the subsidiary to such Person, other than (1)
temporary leases for a term, including renewals at the option of the lessee, of
not more than three years, (2) leases between the Company and a Subsidiary or
between Subsidiaries, (3) leases of a Restricted Property executed by the time
of, or within 12 months after the latest of, the acquisition, the completion of
construction or improvement, or the commencement of commercial operation of the
Restricted Property, and (4) arrangements pursuant to any provision of law with
an effect similar to the former Section 168(f)(8) of the Internal Revenue code
of 1954.



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                "Subsidiary" of any specified corporation, for purposes of the
covenants set forth herein, means (i) a corporation, a majority of whose shares,
interests, rights to purchase, warrants, options, participations or other
equivalents of or interests (however designated) in stock with voting power,
under ordinary circumstances, to elect directors is, at the date of
determination, directly or indirectly owned by the Company, by one or more
Subsidiaries of the Company or by the Company and one or more Subsidiaries of
the Company or (ii) a partnership in which the Company or a Subsidiary of the
Company is at the date of determination, a general partner of such partnership,
or (iii) any other Person (other than a corporation or a partnership) in which
the Company, a Subsidiary of the Company or the Company and one or more
Subsidiaries of the Company, directly or indirectly, at the date of
determination, has (x) at least a majority ownership interest or (y) the power
to elect or direct the election of a majority of the directors or other
governing body of such Person.

                "Value" means, with respect to a Sale and Leaseback Transaction,
an amount equal to the present value of the lease payments with respect to the
term of the lease remaining on the date as of which the amount is being
determined, without regard to any renewal or extension options contained in the
lease, discounted at the weighted average interest rate on the Securities of all
series (including the effective rate on any original issue discount Securities)
which are outstanding on the effective date of such Sale and Leaseback
Transaction and which have the benefit of the provisions herein.

                The Indenture and the Officers' Certificate contain provisions
for defeasance of the entire indebtedness of this Security or certain
restrictive covenants with respect to this Security, in each case upon
compliance with certain conditions set forth in the Indenture.

                If an Event of Default with respect to Securities of this series
shall occur and be continuing, the principal of the Securities of this series
may be declared due and payable in the manner and with the effect provided in
the Indenture. In addition, during the continuance of an Event of Default,
Holders of Securities will be entitled to request and receive individual
definitive Registered Securities.



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                The Indenture permits, with certain exceptions as therein
provided, the amendment thereof and the modification of the rights and
obligations of the Company and the rights of the Holders of the Securities of
each series to be affected under the Indenture at any time by the Company and
the Trustee with the consent of the Holders of a majority in principal amount of
the Securities at the time Outstanding of each series to be affected. The
Indenture also contains provisions permitting the Holders of specified
percentages in principal amount of the Securities of each series at the time
Outstanding, on behalf of the Holders of all Securities of such series, to waive
compliance by the Company with certain provisions of the Indenture and certain
past defaults under the Indenture and their consequences. Any such consent or
waiver by the Holder of this Security shall be conclusive and binding upon such
Holder and upon all future Holders of this Security and of any Security issued
upon the transfer hereof or in exchange herefor or in lieu hereof, whether or
not notation of such consent or waiver is made upon this Security.

                As provided in and subject to the provisions of the Indenture,
the Holder of this Security shall not have the right to institute any proceeding
with respect to the Indenture or for the appointment of a receiver or trustee or
for any other remedy thereunder, unless such Holder shall have previously given
the Trustee written notice of a continuing Event of Default with respect to the
Securities of this series, the Holders of not less than 25% in principal amount
of the Securities of this series at the time Outstanding shall have made written
request to the Trustee to institute proceedings in respect of such Event of
Default as Trustee and offered the Trustee reasonable indemnity, and the Trustee
shall not have received from the Holders of a majority in principal amount of
Securities of this series at the time Outstanding a direction inconsistent with
such request, and shall have failed to institute any such proceeding, for 60
days after receipt of such notice, request and offer of indemnity. The foregoing
shall not apply to any suit instituted by the Holder of this Security for the
enforcement of any payment of principal hereof or any premium or interest hereon
on or after the respective due dates expressed herein.

                No reference herein to the Indenture and no provision of this
Security or of the Indenture shall alter or impair the obligation of the
Company, which is absolute



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and unconditional, to pay the principal of and any premium and interest on this
Security at the times, place and rate, and in the coin or currency, herein
prescribed.

                As provided in the Indenture and subject to certain limitations
therein set forth, the transfer of this Security is registrable in the Security
Register, upon surrender of this Security for transfer at the office or agency
of the Company in any place where the principal of and any premium and interest
on this Security are payable, duly endorsed by, or accompanied by a written
instrument of transfer in form satisfactory to the Company and the Security
Registrar duly executed by, the Holder hereof or his attorney duly authorized in
writing, and thereupon one or more new Securities of this series and of like
tenor, of authorized denominations and for the same aggregate principal amount,
will be issued to the designated transferee or transferees.

                The Securities of this series are issuable only in registered
form without coupons in denominations of $1,000 and any integral multiple
thereof. As provided in the Indenture and subject to certain limitations therein
set forth, Securities of this series are exchangeable for a like aggregate
principal amount of Securities of this series and of like tenor of a different
authorized denomination, as requested by the Holder surrendering the same.

                No service charge shall be made for any such transfer or
exchange, but the Company may require payment of a sum sufficient to cover any
tax or other governmental charge payable in connection therewith.

                Prior to due presentment of this Security for transfer, the
Company, the Trustee and any agent of the Company or the Trustee may treat the
Person in whose name this Security is registered as the owner hereof for all
purposes, whether or not this Security be overdue, and neither the Company, the
Trustee nor any such agent shall be affected by notice to the contrary.

                All terms used in this Security which are defined in the
Indenture shall have the meanings assigned to them in the Indenture.

                THIS INDENTURE AND THE SECURITIES SHALL BE GOVERNED BY AND
CONSTRUED IN ACCORDANCE WITH THE LAW OF THE STATE OF NEW YORK.



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