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                                                                     Exhibit 4.1

================================================================================

                       ADVANTA BUSINESS CARD MASTER TRUST

                                    as Issuer

                                       and

                      DEUTSCHE BANK TRUST COMPANY AMERICAS

                              as Indenture Trustee

                         CLASS A(2005-A4) TERMS DOCUMENT

                          dated as of December 6, 2005

                                       to

                       ADVANTASERIES INDENTURE SUPPLEMENT

                          dated as of November 1, 2004

                                       to

                                    INDENTURE

                           dated as of August 1, 2000

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                                TABLE OF CONTENTS

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                                                                            PAGE
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<S>                                                                         <C>
                                    ARTICLE I
             Definitions and Other Provisions of General Application

Section 1.01 Definitions.................................................     3
Section 1.02 Governing Law...............................................     5
Section 1.03 Counterparts................................................     6
Section 1.04 Ratification of Master Indenture and AdvantaSeries Indenture
             Supplement..................................................     6

                                   ARTICLE II
                     The Class A(2005-A4) Asset Backed Notes

Section 2.01 Creation and Designation....................................     7
Section 2.02 Interest Payment............................................     7
Section 2.03 [Reserved]..................................................     7
Section 2.04 Required Deposits of Available Principal Collections to the
             Principal Funding Account; Payment of Principal.............     7
Section 2.05 Holders' Rights to Payments of Interest and Principal.......     8
Section 2.06 Cash Collateral Account.....................................     8
Section 2.07 Spread Account..............................................     8
Section 2.08 Delivery and Payment for the Class A(2005-A4) Notes; Form
             and Denomination............................................     9
Section 2.09 Manner of Payment of Class A(2005-A4) Notes.................     9
Section 2.10 Monthly Servicing Fee.......................................     9
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                                       -2-

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     CLASS A(2005-A4) TERMS DOCUMENT, dated as of December 6, 2005 (the "TERMS
DOCUMENT"), between WILMINGTON TRUST COMPANY, as Owner Trustee of ADVANTA
BUSINESS CARD MASTER TRUST, a common law trust organized and existing under the
laws of the State of Delaware (herein, the "ISSUER" or the "TRUST"), and
DEUTSCHE BANK TRUST COMPANY AMERICAS (formerly known as Bankers Trust Company),
a banking corporation organized and existing under the laws of the State of New
York, not in its individual capacity, but solely as indenture trustee (herein,
together with its successors in the trusts thereunder as provided in the Master
Indenture, (the "INDENTURE TRUSTEE")) under the Master Indenture, dated as of
August 1, 2000 (the "MASTER INDENTURE") between the Issuer and the Indenture
Trustee. This Terms Document supplements the AdvantaSeries Indenture Supplement,
dated as of November 1, 2004 (the "ADVANTASERIES INDENTURE SUPPLEMENT") between
the Issuer and the Indenture Trustee, which supplements the Indenture.

     Pursuant to this Terms Document, the Issuer shall create a new tranche of
Class A Notes and shall specify the principal terms thereof.

                                    ARTICLE I
             Definitions and Other Provisions of General Application

     Section 1.01 Definitions. For all purposes of this Terms Document, except
as otherwise expressly provided or unless the context otherwise requires:

          (1) the terms defined in this Article have the meanings assigned to
them in this Article, and include the plural as well as the singular;

          (2) all other terms used herein which are defined in the AdvantaSeries
Indenture Supplement or the Master Indenture, either directly or by reference
therein, have the meanings assigned to them therein;

          (3) all accounting terms not otherwise defined herein have the
meanings assigned to them in accordance with generally accepted accounting
principles and, except as otherwise herein expressly provided, the term
"generally accepted accounting principles" with respect to any computation
required or permitted hereunder means such accounting principles as are
generally accepted in the United States of America at the date of such
computation;

          (4) all references in this Terms Document to designated "Articles,"
"Sections" and other subdivisions are to the designated Articles, Sections and
other subdivisions of this Terms Document;

          (5) the words "herein," "hereof" and "hereunder" and other words of
similar import refer to this Terms Document as a whole and not to any particular
Article, Section or other subdivision;

          (6) in the event that any term or provision contained herein shall
conflict with or be inconsistent with any term or provision contained in the
AdvantaSeries Indenture Supplement, the Master Indenture or the Transfer and
Servicing Agreement, the terms and provisions of this Terms Document shall be
controlling;


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          (7) each capitalized term defined herein shall relate only to the
Class A(2005-A4) Notes and no other Tranche of Notes issued by the Issuer; and

          (8) "including" and words of similar import will be deemed to be
followed by "without limitation."

     "Accumulation Amount" shall mean, for any Payment Date occurring during the
Accumulation Period, $18,750,000; provided, however, that if the Accumulation
Period Length is determined to be less than 8 months pursuant to Section
2.04(b), the Accumulation Amount for each Payment Date with respect to the
Accumulation Period will be equal to (i) the Outstanding Principal Balance of
the Class A(2005-A4) Notes divided by (ii) the Accumulation Period Length.

     "Accumulation Deposit Amount" means, for any Payment Date occurring during
the Accumulation Period, an amount equal to the sum of the Accumulation Amount
for such Payment Date and any existing Accumulation Shortfall.

     "Accumulation Period" shall mean, unless a Pay Out Event shall have
occurred prior thereto, the period commencing at the close of business on May
31, 2007, or such later date as is determined in accordance with Section
2.04(b), and ending on the first to occur of (a) the commencement of the Early
Amortization Period, (b) the payment in full of the Outstanding Principal
Balance of the Class A(2005-A4) Notes and (c) the Class A(2005-A4) Final
Maturity Date.

     "Accumulation Period Factor" shall mean, for the purpose of calculating the
Accumulation Period Length for the Class A(2005-A4) Notes, with respect to any
Monthly Period, a fraction, the numerator of which is equal to the sum of the
initial invested amounts (or, if no initial invested amount is defined in the
applicable Indenture Supplement, then the initial principal balance) of all
outstanding Series, and the denominator of which is equal to the sum of (a) the
Initial Principal Balance of Class A(2005-A4) Notes, (b) the initial invested
amounts (or, if no initial invested amount is defined in the applicable
Indenture Supplement, then the initial principal balance) of all other
Outstanding Classes and Tranches (without duplication) (other than the
AdvantaSeries Class A(2005-A4) Notes) which are not expected to be in their
revolving periods, and (c) the initial invested amounts (or, if no initial
invested amount is defined in the applicable Indenture Supplement, then the
initial principal balance) of all other Outstanding Classes and Tranches
(without duplication) (other than the AdvantaSeries Class A(2005-A4) Notes)
which are not allocating Shared Principal Collections to other Series and are in
their revolving periods; provided, however, that this definition may be changed
at any time if the Rating Agency Condition is satisfied.

     "Accumulation Period Length" means the number of whole months such that the
sum of the Accumulation Period Factors for each month during such period will be
equal to or greater than the Required Accumulation Factor Number; provided,
however, that the Accumulation Period Length will not be determined to be less
than one month; provided further, however, that the determination of the
Accumulation Period Length may be changed at any time if the Rating Agency
Condition is satisfied.


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     "Accumulation Shortfall" shall mean (a) on the first Payment Date during
the Accumulation Period, zero and (b) on each subsequent Payment Date during the
Accumulation Period, the excess, if any, of the Accumulation Deposit Amount for
the previous Payment Date over the amount deposited into the Principal Funding
Account pursuant to Section 2.04(b) for the previous Payment Date.

     "AdvantaSeries Indenture Supplement" means the AdvantaSeries Indenture
Supplement dated as of November 1, 2004, by and between the Issuer and the
Indenture Trustee, as amended and supplemented from time to time.

     "Class A(2005-A4) Final Maturity Date" means January 20, 2011.

     "Class A(2005-A4) Note" means any Note substantially in the form set forth
in Exhibit A-1 to the AdvantaSeries Indenture Supplement, designated therein as
a Class A(2005-A4) Asset Backed Note and duly executed and authenticated in
accordance with the Master Indenture.

     "Class A(2005-A4) Noteholder" means a Person in whose name a Class
A(2005-A4) Note is registered in the Note Register.

     "Class A(2005-A4) Note Interest Rate" means a rate per annum equal to
4.75%.

     "Class A(2005-A4) Termination Date" means the earliest to occur of (a) the
Principal Payment Date on which the Outstanding Principal Balance of the Class
A(2005-A4) Notes is paid in full, (b) the Class A(2005-A4) Final Maturity Date
and (c) the date on which the Master Indenture is discharged and satisfied
pursuant to Article XI thereof.

     "Closing Date" means December 6, 2005.

     "Expected Final Principal Payment Date" means February 20, 2008.

     "Initial Principal Balance" means $150,000,000.

     "Interest Payment Date" means the scheduled due date of any payment of
interest on the Class A(2005-A4) Notes, which shall be each Payment Date. The
first Interest Payment Date shall be January 20, 2006.

     "Paying Agent" means Deutsche Bank Trust Company Americas.

     "Required Accumulation Factor Number" shall be equal to a fraction, rounded
upwards to the nearest whole number, the numerator of which is one and the
denominator of which is equal to the lowest monthly principal payment rate on
the Accounts, expressed as a decimal, for the twelve months preceding the date
of such calculation; provided, however, that this definition may be changed at
any time if the Rating Agency Condition is satisfied.

     Section 1.02 Governing Law. THIS TERMS DOCUMENT WILL BE CONSTRUED IN
ACCORDANCE WITH AND GOVERNED BY THE LAWS OF THE STATE OF NEW YORK, INCLUDING
SECTION 5-1401 OF THE GENERAL OBLIGATION LAW, WITHOUT REFERENCE TO ITS CONFLICT
OF LAW PROVISIONS AND THE


                                       -5-

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OBLIGATIONS, RIGHTS AND REMEDIES OF THE PARTIES HEREUNDER SHALL BE DETERMINED IN
ACCORDANCE WITH SUCH LAWS.

     Section 1.03 Counterparts. This Terms Document may be executed in any
number of counterparts, each of which so executed will be deemed to be an
original, but all such counterparts will together constitute but one and the
same instrument.

     Section 1.04 Ratification of Master Indenture and AdvantaSeries Indenture
Supplement. As supplemented by this Terms Document, each of the Master Indenture
and the AdvantaSeries Indenture Supplement is in all respects ratified and
confirmed and the Master Indenture as so supplemented by the AdvantaSeries
Indenture Supplement and this Terms Document shall be read, taken and construed
as one and the same instrument.

                               [END OF ARTICLE I]


                                       -6-

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                                   ARTICLE II
                     The Class A(2005-A4) Asset Backed Notes

     Section 2.01 Creation and Designation. There is hereby created a tranche of
Class A Notes to be issued pursuant to the Master Indenture and the
AdvantaSeries Indenture Supplement to be known as the "AdvantaSeries Class
A(2005-A4) Asset Backed Notes."

     Section 2.02 Interest Payment. For each Interest Payment Date other than
the first Interest Payment Date, the amount of interest due and payable with
respect to the Class A(2005-A4) Notes shall be an amount equal to the product of
(i) (A) a fraction, the numerator of which is thirty (30) and the denominator of
which is 360, multiplied by (B) the Class A(2005-A4) Note Interest Rate,
multiplied by (ii) the Outstanding Principal Balance of the Class A(2005-A4)
Notes determined as of the Record Date preceding the related Interest Payment
Date. Any interest on the Class A(2005-A4) Notes will be calculated on the basis
of a 360-day year and twelve 30-day Interest Periods. For the first Interest
Payment Date, interest on the Class A(2005-A4) Notes will be $870,833.33.

     Section 2.03 [Reserved].

     Section 2.04 Required Deposits of Available Principal Collections to the
Principal Funding Account; Payment of Principal. With respect to any Payment
Date, the amount to be deposited in the Principal Funding Sub-Account pursuant
to Section 4.16 of the AdvantaSeries Indenture Supplement will be the amount
determined pursuant to clause (a), (b), (c) or (d) below for such Payment Date,
as applicable, or if more than one such clause is applicable, the highest amount
determined pursuant to any one of such clauses; provided, however, in no case
shall the amount required to be deposited exceed the Class A(2005-A4) Adjusted
Invested Amount (calculated immediately before giving effect to such deposit but
after giving effect to any Investor Charge-Offs and any reallocations of
principal on such date).

     (a) Revolving Period. On each Payment Date during the Revolving Period, the
required deposit to the Principal Funding Sub-Account for the Class A(2005-A4)
Notes will be zero.

     (b) Accumulation Period. On each Payment Date during the Accumulation
Period, the required deposit to the Principal Funding Sub-Account for the Class
A(2005-A4) Notes will be the Accumulation Deposit Amount for such Payment Date.
The Accumulation Period is scheduled to commence at the close of business on May
31, 2007, provided, however, that, if the Accumulation Period Length is less
than 8 months, the date on which the Accumulation Period actually commences will
be delayed to the close of business on the last day of the month prior to the
month that is the number of whole months prior to the Expected Final Principal
Payment Date which is at least equal to the Accumulation Period Length and, as a
result, the number of Monthly Periods in the Accumulation Period will at least
equal the Accumulation Period Length. On the Determination Date twelve (12)
months prior to the Expected Final Principal Payment Date and each Determination
Date thereafter until the Accumulation Period begins, the Servicer shall
determine the Accumulation Period Length.


                                       -7-

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     (c) Early Amortization Period. On each Payment Date during an Early
Amortization Period, the required deposit to the Principal Funding Sub-Account
for the Class A(2005-A4) Notes will be the Adjusted Invested Amount for the
Class A(2005-A4) Notes as of the close of business on the last day of the
preceding Monthly Period (after taking into account any reductions or increases
occurring on such date).

     (d) Coverage Funding of the Principal Funding Account of Senior Classes. If
the Transferor determines as of the end of the related Monthly Period that,
after giving effect to all allocations and payments with respect to that Monthly
Period, the Coverage Funding Required Amount of the Class A(2005-A4) Notes will
be greater than zero, the required deposit to the Principal Funding Sub-Account
for the Class A(2005-A4) Notes will be the Coverage Funding Required Amount for
such Class A(2005-A4) Notes.

     (e) Distributions to Paying Agent. On each Principal Payment Date, the
Indenture Trustee, acting in accordance with written instructions from the
Servicer, shall withdraw from the Principal Funding Sub-Account for the Class
A(2005-A4) Notes and distribute to the Paying Agent for payment to the Class
A(2005-A4) Noteholders the amounts deposited into the Principal Funding
Sub-Account for the Class A(2005-A4) Notes pursuant to this Section 2.04.

     Section 2.05 Holders' Rights to Payments of Interest and Principal.

     (a) Any installment of interest or principal, if any, payable on any Class
A(2005-A4) Note which is punctually paid or duly provided for by the Issuer and
the Indenture Trustee on the applicable Interest Payment Date or Principal
Payment Date shall be paid by the Paying Agent to the Person in whose name such
Class A(2005-A4) Note (or one or more Predecessor Notes) is registered on the
Record Date, by wire transfer of immediately available funds to such Person's
account as has been designated by written instructions received by the Paying
Agent from such Person not later than the close of business on the third
Business Day preceding the date of payment or, if no such account has been so
designated, by check mailed first-class, postage prepaid to such Person's
address as it appears on the Note Register on such Record Date, except that with
respect to Notes registered on the Record Date in the name of the nominee of
Cede & Co., payment shall be made by wire transfer in immediately available
funds to the account designated by such nominee.

     (b) The right of the Class A(2005-A4) Noteholders to receive payments from
the Issuer will terminate on the first Business Day following the Class
A(2005-A4) Termination Date.

     Section 2.06 Cash Collateral Account. In accordance with Section 4.22(a) of
the AdvantaSeries Indenture Supplement, on or prior to the Closing Date, the
Transferor shall deposit, cause to be deposited or maintain funds in the Cash
Collateral Account such that immediately after giving effect to the issuance of
the Class A(2005-A4) Notes, the amount on deposit in the Cash Collateral Account
for the AdvantaSeries is at least equal to the Required Cash Collateral Account
Amount.

     Section 2.07 Spread Account. In accordance with Section 4.24(a) of the
AdvantaSeries Indenture Supplement, on or prior to the Closing Date, the
Transferor shall deposit, cause to be


                                       -8-

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deposited or maintain funds in the Spread Account such that immediately after
the issuance of the Class A(2005-A4) Notes, the ratio of the amount on deposit
in the Spread Account to the Required Spread Account Amount is equal to or
greater than the same ratio immediately preceding such issuance.

     Section 2.08 Delivery and Payment for the Class A(2005-A4) Notes; Form and
Denomination.

     (a) The Issuer shall execute and issue, and the Indenture Trustee shall
authenticate, the Class A(2005-A4) Notes in accordance with Section 2.03 of the
Master Indenture. The Indenture Trustee shall deliver the Class A(2005-A4) Notes
to or upon the order of the Issuer when so authenticated. The Class A(2005-A4)
Notes shall be Book-Entry Notes.

     (b) The Depository for the Class A(2005-A4) Notes shall be The Depository
Trust Company, and the Class A(2005-A4) Notes shall initially be registered in
the name of Cede & Co., its nominee.

     (c) The Class A(2005-A4) Notes will be issued in minimum denominations of
$5,000 and integral multiples of $1,000 in excess of that amount.

     Section 2.09 Manner of Payment of Class A(2005-A4) Notes. Except as
provided in Section 11.02 of the Master Indenture with respect to a final
distribution, distributions to Class A(2005-A4) Noteholders hereunder shall be
made by (i) check mailed to each Class A(2005-A4) Noteholder (at such
Noteholder's address as it appears in the Note Register), except that with
respect to any Class A(2005-A4) Notes registered in the name of the nominee of a
Clearing Agency, such payment shall be made in immediately available funds and
(ii) without presentation or surrender of any Class A(2005-A4) Note or the
making of any notation thereon.

     Section 2.10 Monthly Servicing Fee. In accordance with Section 3.01(a) of
the AdvantaSeries Indenture Supplement, with respect to the January 20, 2006
Payment Date, the AdvantaSeries Monthly Servicing Fee allocated to the Class
A(2005-A4) Notes shall be $208,333.

                               [END OF ARTICLE II]


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     IN WITNESS WHEREOF, the undersigned have caused this Terms Document to be
duly executed and delivered by their respective duly authorized officers on the
day and year first above written.

                                       WILMINGTON TRUST COMPANY,
                                          as Owner Trustee of
                                       ADVANTA BUSINESS CARD MASTER TRUST


                                       By: /s/ Dorri Wolhar
                                           -------------------------------------
                                       Name:   Dorri Wolhar
                                       Title:  Financial Services Officer


                                       DEUTSCHE BANK TRUST COMPANY AMERICAS,
                                          as Indenture Trustee


                                       By: /s/ Jenna Kaufman
                                           -------------------------------------
                                       Name:   Jenna Kaufman
                                       Title:  Vice President

               [Signature Page to Class A(2005-A4) Terms Document]