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                                      EXHIBIT A


                   RELEVANT SUBSIDIARIES OF PARENT HOLDING COMPANY

PART A: TCW ENTITIES

PARENT HOLDING COMPANY:

          The TCW Group, Inc.

          Robert Day (an individual who may be deemed to control The TCW Group, 
          Inc.)


RELEVANT SUBSIDIARIES THAT ARE PERSONS DESCRIBED IN RULE 13d-1(b):

     (i)   Trust Company of the West, a California corporation and a bank as
     defined in Section 3(a)(6) of the Securities Exchange Act of 1934. 

     (ii)  TCW Asset Management Company, a California corporation and an
     Investment Adviser registered under Section 203 of the Investment Advisers
     Act of 1940. 

     (iii) TCW Funds Management, Inc., a California corporation and an
     Investment Adviser registered under Section 203 of the Investment Advisers
     Act of 1940. 
     
Note:     No Common Stock of Bolder Technologies Corp. is held directly by The
          TCW Group, Inc.  Other than the indirect holdings of The TCW Group,
          Inc. no Common Stock of Bolder Technologies Corp. is held directly or
          indirectly by Robert Day, an individual who may be deemed to control
          The TCW Group, Inc. 
     
PART B: NON TCW ENTITIES

PARENT HOLDING COMPANY:

          Robert Day (an individual who may be deemed to control the holders
          described below which are not subsidiaries of The TCW Group, Inc.)

RELEVANT SUBSIDIARIES THAT ARE PERSONS DESCRIBED IN RULE 13d-1(b):

          Oakmont Corporation, a California corporation and an Investment
          Adviser registered under Section 203 of the Investment Advisers Act of
          1940.

          Cypress International Partners Limited, a British Virgin Islands
          corporation and an Investment Adviser registered under Section 203 of
          the Investment Advisers Act of 1940.



                                        A-1
                                          
                                          
