This is a NEW FoMoCo windshield washer bag with the flip cap.  I fits the following Ford ad Mercury vehicles:
NOTE: The build dates are approximate:
Ford Mustang 1965 and 1966
Ford Fairlane 1965-1967 (before Mar 1 1967)
Ford Falcon 1966-1967 (before Mar 1 1967)
Ford Galaxie 1966-1967 (before Mar 1 1967)
Mercury Cougar 1967 (before Nov 1 1966)
Mercury Comet 1967 (before Nov 1 1966)