Non vented fuel cap, P/N MS53075-1. NSN 2590004598447. Used on certain vehicles such as the M809 series, Jeeps, etc. (Make sure your application uses the non-vented design.) Not for the M35A3 or M939 series trucks. Rubber seal is compatible with gasoline and diesel.
Fuel cap is new/unused but may have some tarnish on the metal from storage. Limited to stock on hand.