This is NORS Mopar locking gas cap for the years and station wagon models listed below. New USA made part by Stant Inc. in it’s original packaging.
G56 [same as Chrysler P/n 1820187]
Windsor; Saratoga; Newport, New Yorker, Chrysler 300C; 300D
Fireflite; Firedome; Firesweep; Adventurer
Coronet; Royal; Custom Royal; Royal Lancer; D-500
Savoy; Belvedere; Fury