New Gates valve cover oil fill cap.  This the "cam twist" style cap.  For factory valve covers only.  Fits the following:

84-87 Corvette
84-88 Fiero 4-cylinder
70-81 Firebird/Trans Am w/ 301/400/455 Pontiac engine
77-81 Firebird/Trans Am w/ 305/350 Chevy Engine,
70-81 Firebird w/ V6 engine
77-79 Trans Am w/ 403 Oldsmobile engine (on oil filler tube on block)
82-88 Camaro w/ 305/350 Chevrolet engine
82-88 Firebird/Trans Am w/ 305/350 Chevrolet engine
82-85 Camaro w/ 4 cylinder
82-85 Firebird w/ 4-cylinder