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Rule 497 (d)
NATIONAL MUNICIPAL TRUST, INSURED SERIES 21
SUPPLEMENT TO PROSPECTUS
September 12, 1995
Effective September 1, 1995, the Trustee is The
Chase Manhattan Bank (National Association), a national banking
asociation with its principal executive office located at 1 Chase
Manhattan Plaza, New York, New York 10081 and its unit investment
trust office at 770 Broadway, New York, New York 10003. The
Trustee is subject to supervision by the Comptroller of the
Currency, the Federal Deposit Insurance Corporation and the Board
of Governors of the Federal Reserve System.
The prospectus included in the Registration
Statement for National Municipal Trust, Insured Series 21 is hereby
incorporated by reference.