This is a tail light housing to body seal for 1981-93 Ford Mustangs. This is the one that seals the back of the turn signal opening in the center of the housing. Ford part number E1FZ-13A495-A. Reproduction quality doesn't even come close to the original Ford quality on these seals. 

81-93 Ford Mustang Tail light housing to body seal-NOS Genuine Ford

SKU: 1219tailseal