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                                                                      EXHIBIT 4F


                     ANCHOR NATIONAL LIFE INSURANCE COMPANY

                          OPTIONAL INCOME BENEFIT (OIB)
                                   ENDORSEMENT

This Endorsement is made a part of, and subject to, the other terms and
conditions of the Contract to which it is attached. This Endorsement becomes
effective on the Effective Date. All the terms have the same meanings as in the
Contract except as defined below.

                                 SPECIFICATIONS

CONTRACT NUMBER:                               GROWTH RATE:
     A1111111111                                    [3.25%]

EFFECTIVE DATE:                                OIB CHARGE PERCENTAGE:
      February 6, 2001                             [0.15%]

ENDORSEMENT DATE:                              EARLIEST INCOME BENEFIT DATE:
      February 6, 2000                               February 6, 2008

                                   DEFINITIONS

EFFECTIVE DATE
The Effective Date of the OIB Endorsement is as shown above. If elected at
Contract issue, the Effective Date and the Endorsement Date will be the same as
the Contract Date. If elected after Contract issue, the Effective Date is the
Contract anniversary immediately following the Endorsement Date.

ENDORSEMENT DATE
The Endorsement Date is the date that the OIB Endorsement was issued, as shown
above.

INCOME BENEFIT BASE
The amount We use to determine the OIB, as discussed below.

INCOME BENEFIT DATE
The Contract anniversary date on which the OIB is calculated. The Income Benefit
Date, which is selected by You, must be the [first - fifteenth] Contract
anniversary following the Effective Date of this Endorsement. In order for the
OIB to take effect, the Annuity Date You select must be within the 30 days
following Your Income Benefit Date. The Income Benefit Date must be no later
than the latest Annuity Date as discussed in the ANNUITY PROVISIONS of Your
Contract. To arrange selection of an Income Benefit Date, contact Our Annuity
Service Center.

                                   PROVISIONS

OIB
This Endorsement provides for guaranteed minimum annuity payments under selected
Fixed Annuity Payment Options, which are provided for in Your Contract and
specified in this Endorsement.

We will only provide for the guaranteed minimum annuity payments under the OIB
if You select an Annuity Date which is within 30 days following any Income
Benefit Date, and Your entire Contract Value is to be distributed under one of
the Fixed Annuity Payment Options described in this Endorsement. The Annuity
Date, as defined in Your Contract, is the date selected by You on which Annuity
Payments are to begin.


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On the Annuity Date, the amount of the guaranteed Fixed Annuity payment is
calculated by applying the Income Benefit Base as of the Income Benefit Date, as
described below, reduced by: (a) any Partial Withdrawals of Contract Value
(which include any charges associated with those withdrawals) since the Income
Benefit Date; and (b) any Withdrawal Charges otherwise applicable to amounts in
Your Contract, calculated as if You fully surrender Your Contract as of the
Income Benefit Date; and (c) any applicable premium taxes, to the annuity rates
set forth in this Endorsement.

This amount is compared to the Fixed Annuity payment amount under the same
Annuity Payment Option provided for in the ANNUITY PROVISIONS of Your Contract,
which is calculated, based on Your Contract Value on the Annuity Date. We will
pay whichever is greater. You may also select any other Annuity Payment Option
as outlined in Your Contract to be applied to your actual Contract Value.
However, We will not provide for guaranteed minimum annuity payments under this
OIB.

INCOME BENEFIT BASE
On the Effective Date of this Endorsement, the Income Benefit Base is equal to
the entire Contract Value on that date. If the OIB is elected at Contract issue,
the Income Benefit Base on the Contract Date is the First Purchase Payment.

For purposes of subsequent calculation of the Income Benefit Base, the Income
Benefit Base is equal to (a) plus (b) less (c), where;

     (a) is the Income Benefit Base on the prior Contract anniversary (or the
     Contract Date if being calculated on the first Contract anniversary)
     accumulated at the Growth Rate indicated in the SPECIFICATIONS section of
     this Endorsement, and

     (b) is the sum of all Purchase Payments received after the prior Contract
     anniversary (or after the Contract Date if being calculated on the first
     Contract Anniversary) accumulated at the Growth Rate indicated in the
     SPECIFICATIONS section of this Endorsement, starting on the date each
     Purchase Payment is allocated to the Contract, and

     (c) is the sum of Income Benefit Base reductions made after the prior
     Contract anniversary (or after the Contract Date if being calculated on the
     first Contract anniversary) accumulated at the Growth Rate indicated in the
     SPECIFICATIONS section of this Endorsement, starting on the date each
     deduction occurs.

An Income Benefit Base reduction is calculated on a pro rata basis to
effectively reduce the Income Benefit Base in proportion to the actual reduction
in Contract Value. The reduction is equal to the Income Benefit Base immediately
prior to a Partial Withdrawal of Contract Value (which includes any charges
associated with the withdrawal) multiplied by the percentage reduction in
Contract Value resulting from the Partial Withdrawal of Contract Value.

THE INCOME BENEFIT BASE IS USED SOLELY FOR THE PURPOSE OF CALCULATING THE OIB
AND DOES NOT PROVIDE A CONTRACT VALUE OR GUARANTEE PERFORMANCE OF ANY INVESTMENT
OPTION.

GROWTH RATE
The Growth Rate will be the rate shown in the SPECIFICATIONS section of this
Endorsement through the Contract anniversary immediately following the
Annuitant's 90th birthday. The Growth Rate is reduced to 0.00% on the Contract
anniversary immediately following the Annuitant's 90th birthday.


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OIB CHARGE
This annual charge is to compensate Us for the risk assumed as a result of
contractual obligations to provide the OIB. The OIB Charge Percentage will never
be greater than the percentage shown on the SPECIFICATIONS section of this
Endorsement. The OIB Charge equals the OIB Charge Percentage multiplied by the
Income Benefit Base in effect on that Contract anniversary. The OIB Charge is
deducted from the Contract Value annually, on each Contract anniversary. This
charge is no longer deducted after the Annuity Date.

Upon Total Withdrawal of the Contract Value, We will deduct the OIB Charge from
the Contract Value. If the Total Withdrawal of the Contract Value is requested
on any date other than the Contract anniversary, this charge will be calculated
based on the Income Benefit Base immediately prior to the Total Withdrawal and
will not be prorated.

TERMINATION
Once elected, You cannot terminate this OIB option.

                        OIB FIXED ANNUITY PAYMENT OPTIONS

OPTION 1  - LIFE ANNUITY WITH PAYMENTS GUARANTEED FOR  10 YEARS
Payments are payable to the Payee during the lifetime of the Annuitant. If, at
the death of the Annuitant, payments have been made for less than 10 years, the
remaining guaranteed annuity payments will be continued to the Beneficiary.

OPTION 2 - JOINT AND SURVIVOR LIFE ANNUITY WITH PAYMENTS GUARANTEED FOR 20 YEARS
Payments are payable to the Payee during the lifetime of the Annuitant and
during the lifetime of a designated second person. If, at the death of the
survivor, payments have been made for less than 20 years, the remaining
guaranteed annuity payments will be continued to the Beneficiary.


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                     OIB FIXED ANNUITY PAYMENT OPTIONS TABLE


BASIS OF COMPUTATION
The actuarial basis for the Table of Annuity Rates is the 1983a Annuity
Mortality Table with projection and a guaranteed interest rate of 2.25%. The
mortality table is projected using Projection Scale G factors, assuming
annuitization in the year 2000. The OIB Fixed Annuity Payment Options Table does
not reflect any applicable premium tax.

              OPTION 1 - TABLE OF MONTHLY INSTALLMENTS PER $1,000.
    (MONTHLY INSTALLMENTS FOR AGES NOT SHOWN WILL BE FURNISHED UPON REQUEST)
                    LIFE ANNUITY (W/120 PAYMENTS GUARANTEED)

<TABLE>
<CAPTION>

        AGE OF                                                   AGE OF
      ANNUITANT             MALE               FEMALE           ANNUITANT              MALE              FEMALE
<S>                         <C>                <C>               <C>                 <C>                <C>
         55                 3.76                3.39                71                 5.72               5.05
         56                 3.84                3.46                72                 5.90               5.21
         57                 3.93                3.53                73                 6.07               5.38
         58                 4.02                3.60                74                 6.25               5.56
         59                 4.12                3.68                75                 6.43               5.75
         60                 4.22                3.76                76                 6.62               5.94
         61                 4.33                3.85                77                 6.81               6.14
         62                 4.44                3.94                78                 6.99               6.34
         63                 4.56                4.04                79                 7.18               6.55
         64                 4.68                4.14                80                 7.36               6.76
         65                 4.81                4.25                81                 7.54               6.97
         66                 4.95                4.37                82                 7.72               7.18
         67                 5.09                4.49                83                 7.88               7.39
         68                 5.24                4.62                84                 8.04               7.58
         69                 5.40                4.75                85                 8.19               7.77
         70                 5.56                4.90

</TABLE>


              OPTION 2 - TABLE OF MONTHLY INSTALLMENTS PER $1,000.
    (MONTHLY INSTALLMENTS FOR AGES NOT SHOWN WILL BE FURNISHED UPON REQUEST)
         JOINT & 100% SURVIVOR LIFE ANNUITY (W/240 PAYMENTS GUARANTEED)

<TABLE>
<CAPTION>

      AGE OF
       MALE
    ANNUITANT                                             AGE OF FEMALE ANNUITANT
                           55            60            65            70           75           80            85
<S>                      <C>           <C>           <C>           <C>          <C>          <C>           <C>
        55                3.11          3.27          3.40          3.51         3.58         3.62          3.63
        60                3.20          3.40          3.60          3.76         3.88         3.94          3.97
        65                3.26          3.51          3.77          4.00         4.18         4.28          4.32
        70                3.30          3.58          3.89          4.19         4.44         4.58          4.65
        75                3.33          3.63          3.97          4.32         4.62         4.81          4.90
        80                3.34          3.65          4.01          4.39         4.72         4.94          5.04
        85                3.34          3.65          4.02          4.41         4.76         4.99          5.10

</TABLE>



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All other terms and conditions of the Contract remain unchanged. Signed for the
Company at Los Angeles, California.



    /s/  CHRISTINE A. NIXON                   /s/ JAY S. WINTROB
---------------------------------         -----------------------------
       Christine A. Nixon                       Jay S. Wintrob
           Secretary                              President



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