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                                                                    EXHIBIT 10.6

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                      NISSAN MOTOR ACCEPTANCE CORPORATION,

                               NISSAN-INFINITI LT,

                                   NILT TRUST,

                           NISSAN AUTO LEASING LLC II,

                         NISSAN AUTO LEASE TRUST 2004-A,

                                       and

                         U.S. Bank National Association,
                              as Indenture Trustee

                        ---------------------------------

                           BACK-UP SECURITY AGREEMENT

                          Dated as of October 28, 2004

                        ---------------------------------

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<TABLE>
<S>                                                                                           <C>
                                    ARTICLE I

                                   DEFINITIONS

1.01     Definitions.....................................................................     2
1.02     Interpretive Provisions.........................................................     2

                                   ARTICLE II

                                SECURITY INTEREST

2.01     Grant of Security Interest......................................................     2
2.02     Certificate of Title............................................................     3
2.03     Filing of Financing Statements..................................................     3
2.04     Use of Collateral...............................................................     3
2.05     Further Description of the Collateral...........................................     3
2.06     Back-Up Rights of Indenture Trustee.............................................     4

                                   ARTICLE III

                                  MISCELLANEOUS

3.01     Amendments......................................................................     4
3.02     Governing Law...................................................................     4
3.03     Severability of Provisions......................................................     4
3.04     Counterparts....................................................................     4
3.05     Successors and Assigns..........................................................     4
3.06     Further Assurances..............................................................     4
3.07     Limitation of Liability of Owner Trustee........................................     4
3.08     Notices.........................................................................     5
</TABLE>

                                        i

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                           BACK-UP SECURITY AGREEMENT

      This Back-Up Security Agreement, dated as of October 28, 2004, is among
Nissan Motor Acceptance Corporation, a California corporation ("NMAC"),
Nissan-Infiniti LT, a Delaware statutory trust (the "Titling Trust"), NILT
Trust, a Delaware statutory trust ("NILT Trust"), Nissan Auto Leasing LLC II, a
Delaware limited liability company ("NALL II"), Nissan Auto Lease Trust 2004-A,
a Delaware statutory trust (the "Trust"), and U.S. Bank National Association
("U.S. Bank"), as trustee (the "Indenture Trustee") under the Indenture, dated
as of October 28, 2004 (the "Indenture"), between the Trust and the Indenture
Trustee.

                                    RECITALS

      WHEREAS, NILT Trust, as Grantor and UTI Beneficiary, NMAC, as Servicer,
Wilmington Trust Company, as Delaware Trustee, NILT, Inc., as Trustee, and U.S.
Bank, as Trust Agent, have entered into an amended and restated trust and
servicing agreement, dated as of August 26, 1998 (the "Titling Trust
Agreement"), pursuant to which the Titling Trust was created to, among other
things, take assignments and conveyances of and hold in trust various assets
(the "Trust Assets");

      WHEREAS, the parties to the Titling Trust Agreement supplemented the
Titling Trust Agreement with a 2004-A SUBI Supplement, dated as of October 28,
2004 (together with the Titling Trust Agreement, the "SUBI Trust Agreement"), to
establish a special unit of beneficial interest, the "2004-A SUBI" ("2004-A
SUBI");

      WHEREAS, in connection with the SUBI Trust Agreement a separate portfolio
of leases (the "2004-A Leases"), the vehicles that are leased under the 2004-A
Leases (the "2004-A Vehicles"), and certain other related Trust Assets have been
allocated to the 2004-A SUBI;

      WHEREAS, the Titling Trust has issued a certificate evidencing a 100%
beneficial interest in the 2004-A SUBI (the "2004-A SUBI Certificate") to NILT
Trust;

      WHEREAS, the Trust was formed pursuant to a trust agreement, dated as of
July 28, 2004, as amended and restated as of October 28, 2004 (the "Trust
Agreement"), between NALL II and Wilmington Trust Company, as Owner Trustee;

      WHEREAS, pursuant to the SUBI Certificate Transfer Agreement, dated as of
October 28, 2004 (the "SUBI Certificate Transfer Agreement"), between NILT Trust
and NALL II, NILT Trust has transferred and assigned to NALL II, without
recourse, all of NILT Trust's right, title and interest in the 2004-A SUBI
Certificate;

      WHEREAS, pursuant to the Trust SUBI Certificate Transfer Agreement, dated
as of October 28, 2004 (the "Trust SUBI Certificate Transfer Agreement"),
between NALL II, as transferor (the "Transferor") and the Trust, as transferee,
the Transferor has transferred and assigned to the Trust, without recourse, all
of the Transferor's right, title and interest in the 2004-A SUBI Certificate;

                                                      Back-Up Security Agreement

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      WHEREAS, pursuant to the Indenture, the Trust has granted a security
interest in the 2004-A SUBI Certificate to the Indenture Trustee to secure
payment of the Notes;

      WHEREAS, the parties hereto desire to enter into this Agreement to provide
that if, for any reason, the form of any of the transactions contemplated by the
SUBI Trust Agreement, the 2004-A SUBI Certificate, the Trust Agreement, the SUBI
Certificate Transfer Agreement, the Trust SUBI Certificate Transfer Agreement or
the Indenture (collectively, the "Transfer Documents") is deemed to constitute a
loan by any or all of the Securityholders, secured by a pledge of the 2004-A
SUBI Assets or any interest therein (rather than by the 2004-A SUBI
Certificate), each of NMAC, the Titling Trust, NILT Trust, the Transferor and
the Trust shall be deemed to have granted to the Indenture Trustee a first
priority security interest in such assets to secure the Notes.

      NOW, THEREFORE, in consideration of the mutual agreements herein
contained, and of other good and valuable consideration, the receipt and
adequacy of which are hereby acknowledged, the parties hereto agree as follows:

                                    ARTICLE I
                                   DEFINITIONS

      1.01 Definitions. Capitalized terms used herein that are not otherwise
defined shall have the meanings ascribed thereto in the Agreement of
Definitions, dated as of October 28, 2004, by and among the Trust, as issuer
(the "Issuer"), NILT Trust, as grantor and initial beneficiary (in such
capacity, the "Grantor" and the "UTI Beneficiary," respectively), the Titling
Trust, NMAC, in its individual capacity, as servicer and as administrative agent
(in such capacity, the "Servicer" and the "Administrative Agent," respectively),
NALL II, NILT, Inc., a Delaware corporation, as trustee to the Titling Trust
(the "Trustee"), Wilmington Trust Company, a Delaware banking corporation, as
owner trustee and Delaware trustee (in such capacity, the "Owner Trustee" and
the "Delaware Trustee," respectively) and U.S. Bank, as Indenture Trustee and
trust agent (in such capacity, the "Trust Agent").

      1.02 Interpretive Provisions. For all purposes of this Agreement, except
as otherwise expressly provided or unless the context otherwise requires, (i)
terms used herein include, as appropriate, all genders and the plural as well as
the singular, (ii) references to words such as "herein", "hereof" and the like
shall refer to this Agreement as a whole and not to any particular part, Article
or Section herein, (iii) references to an Article or Section such as "Article
One" or "Section 1.01" shall refer to the applicable Article or Section of this
Agreement, (iv) the term "include" and all variations thereof shall mean
"include without limitation", (v) the term "or" shall include "and/or" and (vi)
the term "proceeds" shall have the meaning ascribed to such term in the UCC.

                                   ARTICLE II
                                SECURITY INTEREST

      2.01 Grant of Security Interest.

                                                      Back-Up Security Agreement

                                        2
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            (a) Each of NMAC, the Titling Trust, NILT Trust, the Transferor and
the Trust hereby grants to the Indenture Trustee a security interest in all of
its present and future right, title and interest in, to and under (but not,
except to the extent required by law, any obligations with respect to) the
following collateral (the "Collateral"): (i) a 100% beneficial interest in (A)
all rights under the 2004-A Leases; (B) to the extent permitted by applicable
law, the 2004-A Vehicles; (C) all other 2004-A SUBI Assets, including the 2004-A
SUBI Collection Account, and (D) all proceeds of the items described in (i) (A),
(B) and (C), including insurance payable by reason of loss or damage to the
2004-A Vehicles to the extent not applied to making repairs to the related
2004-A Vehicle or otherwise paid by the Servicer to the Lessee, a third person
or governmental authority as required by law or pursuant to its normal servicing
practices; (ii) the Reserve Account; (iii) all rights and benefits under the
Interest Rate Cap Agreement; and (iv) all proceeds, accounts, money, general
intangibles, instruments, chattel paper, goods, investment property or other
property consisting of, arising from or related to the foregoing. Such grant is
made to secure (i) the payment of all amounts due on the Securities in
accordance with their terms in the priorities of payment set forth in the
Indenture, (ii) the payment of all other sums payable under the Indenture and
(iii) compliance with the provisions of the Indenture.

            (b) The Indenture Trustee acknowledges such grant and assignment,
but all parties hereto acknowledge and agree that (i) such grant and assignment
are made solely for protective purposes and without representation or warranty
as to the nature of any of parties' rights in and to the Collateral and (ii)
none of the parties hereto intends to imply in any way that any of the Transfer
Documents should not be interpreted or enforced in accordance with its
respective terms. The Indenture Trustee also acknowledges that it shall have no
claim to any proceeds or assets of the Titling Trust or to any of the Trust
Assets other than the 2004-A SUBI Assets and any present or future proceeds
thereof.

      2.02 Certificate of Title. None of the parties hereto, including the
Titling Trust, shall have any obligation or otherwise be required to make
notation on, or cause to be taken any other action with respect to, any
Certificate of Title for any 2004-A Vehicle to reflect the back-up Lien created
hereby.

      2.03 Filing of Financing Statements. Each of NMAC, the Titling Trust, NILT
Trust, the Transferor and the Trust will from time to time execute, deliver and
file all financing statements and continuation statements reasonably required or
necessary to maintain, perfect or continue the perfection of the backup Lien
created hereby with respect to the 2004-A Leases and the proceeds thereof and
any other Collateral, the perfection of a security interest in which may be
accomplished and continued by the same filings.

      2.04 Use of Collateral. Each of the parties granting a security interest
hereunder may continue to use and deal with its interest in the Collateral in
any lawful manner and may sell items of Collateral in the ordinary course of its
business, subject only to the requirements of the Transfer Documents and the
Servicing Agreement, as appropriate.

      2.05 Further Description of the Collateral. A description of the 2004-A
Leases and the 2004-A Vehicles appears on the Schedule of 2004-A Leases and
2004-A Vehicles.

                                                      Back-Up Security Agreement

                                        3
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      2.06 Back-Up Rights of Indenture Trustee. If a Back-Up Event shall have
occurred and be continuing, the Indenture Trustee may exercise the rights and
remedies with respect to the Collateral of a secured party under the UCC to the
extent permitted by applicable law. Notwithstanding any other provision hereof,
the Indenture Trustee shall have recourse only against the Collateral and not
against any Pledgor hereunder (excluding responsibilities of NMAC solely as
Servicer).

                                   ARTICLE III
                                  MISCELLANEOUS

      3.01 Amendments. This Agreement may be amended by written agreement among
the parties hereto; provided, however, that it may only be amended under the
same circumstances the Trust Agreement could be amended pursuant to Section
12.01 thereof and the Indenture could be amended pursuant to Article Nine
thereof.

      3.02 Governing Law. This Agreement shall be governed by and construed in
accordance with the laws of the State of New York, without reference to its
conflict of law provisions (other than Section 5-1401 of the General Obligations
Law of the State of New York).

      3.03 Severability of Provisions. If any one or more of the covenants,
agreements, provisions or terms of this Agreement shall be for any reason
whatsoever held invalid or unenforceable, then such covenants, agreements,
provisions or terms shall be deemed severable from the remaining covenants,
agreements, provisions and terms of this Agreement, as the same may be amended
or supplemented, and shall in no way affect the validity or enforceability of
the other covenants, agreements, provisions or terms of this Agreement.

      3.04 Counterparts. This Agreement may be executed in any number of
counterparts, each of which so executed and delivered shall be deemed to be an
original, but all of which counterparts shall together constitute but one and
the same instrument.

      3.05 Successors and Assigns. All covenants and agreements contained in
this Agreement shall be binding upon, and inure to the benefit of, the parties
hereto and their respective permitted successors and assigns.

      3.06 Further Assurances. Each party will perform such acts and execute and
deliver to any other party such additional documents or instruments as may be
reasonably requested in order to effect the purposes of this Agreement and to
better assure and confirm unto the requesting party its rights, powers and
remedies hereunder.

      3.07 Limitation of Liability of Owner Trustee. Notwithstanding anything
contained herein to the contrary, this instrument has been executed by
Wilmington Trust Company not in its individual capacity but solely in its
capacity as Owner Trustee of the Trust and in no event shall Wilmington Trust
Company in its individual capacity or any beneficial owner of the Trust have any
liability for the representations, warranties, covenants, agreements or other
obligations of the Trust hereunder, as to all of which recourse shall be had
solely to the assets of the Trust. For all purposes of this Agreement, in the
performance of any duties or obligations of the Trust

                                                      Back-Up Security Agreement

                                        4
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hereunder, the Owner Trustee shall be subject to, and entitled to the benefits
of, the terms and provisions of Articles Six, Seven and Ten of the Trust
Agreement.

      3.08 Notices. All notices, requests and demands under this Agreement shall
be given in accordance with Section 11.04 of the Indenture. The address for such
purpose of the Titling Trust shall be c/o NILT, Inc., as Trustee, 209 South
LaSalle Street, Suite 300, Chicago IL 60604 (telecopier no. (312) 325-8905),
Attention: Nissan Auto Lease Trust 2004-A.

                                                      Back-Up Security Agreement

                                        5
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      IN WITNESS WHEREOF, the parties hereto have caused this Agreement to be
duly executed by their respective officers hereto duly authorized, as of the day
and year first above written.

                                        NISSAN MOTOR ACCEPTANCE CORPORATION

                                        By: /s/ Steven R. Lambert
                                            ------------------------------------
                                            Name:  Steven R. Lambert
                                            Title: President

                                        NISSAN-INFINITI LT

                                        By: NILT, INC., as Titling Trustee

                                            By: /s/ Patricia M. Child
                                                --------------------------------
                                            Name: Patricia M. Child
                                            Title: President

                                        NILT TRUST

                                        By: U.S. BANK NATIONAL ASSOCIATION,
                                            as Managing Trustee

                                            By: /s/ Patricia M. Child
                                                --------------------------------
                                            Name: Patricia M. Child
                                            Title: Vice President

                                        NISSAN AUTO LEASING LLC II

                                        By: /s/ Joji Tagawa
                                            ------------------------------------
                                            Name: Joji Tagawa
                                            Title: Treasurer

                                       S-1            Back-Up Security Agreement

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                                        NISSAN AUTO LEASE TRUST 2004-A

                                        By:   Wilmington Trust Company,
                                                not in its individual capacity,
                                                but solely as Owner Trustee

                                              By: /s/ Joann A. Rozell
                                                  -----------------------------
                                              Name: Joann A. Rozell
                                              Title: Financial Services Officer

                                        U.S. BANK NATIONAL
                                        ASSOCIATION, as
                                        Indenture Trustee

                                        By: /s/ Patricia M. Child
                                            -----------------------------------
                                            Name: Patricia M. Child
                                            Title: Vice President

                                       S-2            Back-Up Security Agreement