MAYER, BROWN & PLATT
                            2000 Pennsylvania Avenue
                          Washington, D.C. 20005-1882




                                                  April 21, 1997




VIA EDGAR

Securities and Exchange Commission
450 Fifth Street, N.W.
Washington, D.C.  20549

Dear Sir or Madam:

            Re:      Security Life of Denver Insurance Company
                     Security Life Separate Account A1
                     (File No. 811-8196)

         Transmitted  herewith  for filing  pursuant  to Rule  497(e)  under the
Securities  Act of 1933, as amended,  is a Supplement,  dated April 18, 1997, to
the current  effective  Prospectus  dated May 1, 1996, of Security Life Separate
Account A1 with respect to The Exchequer Variable Annuity (File No. 33-78444).

         Please  contact  me at the  above-referenced  number  if you  have  any
questions concerning this filing.

                                     Sincerely,


                                     /s/ Kathy Kresch Ingber
                                     Kathy Kresch Ingber
                                     Counsel



Attachment
cc:      Edward MacDonald, Esq.





                    SECURITY LIFE OF DENVER INSURANCE COMPANY

                       SUPPLEMENT DATED APRIL 18, 1997, TO
                      THE PROSPECTUS DATED MAY 1, 1996, FOR

                       SECURITY LIFE SEPARATE ACCOUNT L1:
               FIRSTLINE VARIABLE UNIVERSAL LIFE INSURANCE POLICY
          STRATEGIC ADVANTAGE VARIABLE UNIVERSAL LIFE INSURANCE POLICY

                       SECURITY LIFE SEPARATE ACCOUNT A1:
                           EXCHEQUER VARIABLE ANNUITY

This Supplement updates certain information contained in your Prospectus. Please
read it carefully and keep it with your Prospectus for future reference.

Beginning May 1, 1997, the Divisions of the Variable  Accounts  investing in the
Neuberger & Berman Advisers Management Trust Government Income Portfolio and the
Van Eck Worldwide Balanced Fund will no longer accept new investments, including
through  transfers,  automatic  rebalancing or dollar cost averaging.  Unless we
receive  updated  allocation  instructions  from you, we will  allocate  amounts
designated  for these Funds to the other  Funds  designated  in your  allocation
instructions,  in proportion to the amounts indicated for those Funds.  Existing
investments in these Funds will not need to be moved at this time.

Beginning  April 30, 1997,  the Van Eck Gold and Natural  Resources Fund will be
renamed the  Worldwide  Hard  Assets  Fund to reflect the Fund's new  investment
objective and  concentration  policy  approved by shareholders on April 9, 1997.
The  Fund's  new  investment   objective  will  be  to  seek  long-term  capital
appreciation by investing globally, primarily in "hard asset" securities. Income
would be a secondary consideration. The Fund will now invest at least 25% of its
assets  in  companies  engaged  to a  significant  extent  in  the  exploration,
development,  production or  distribution  of one or more of the following "hard
asset" sectors:  (1) precious metals; (2) ferrous metals and non-ferrous metals;
(3) oil and gas;  (4) forest  products;  (5) real  estate;  and (6) other  basic
non-agricultural  commodities.  The Fund also will have the ability to invest in
indexed securities and swaps and will have increased flexibility with respect to
investment in illiquid  securities and will expand other of its  non-fundamental
investment restrictions.