This square port, reusable, header gasket set creates a tight seal around header flanges to protect against leaks. Engineered with a dual layer design to conform to header flanges, even with minor surface imperfections for a superior seal. Made from soft conforming aluminum. Provides advanced protection from blowouts, burnouts and deterioration, making them ideal for the street or the strip. Use with PROFORM's Wedge-Locking Header Bolts, to create ultimate combo of headers that don't come loose, and an ideal seal! For Small Block Chevy 262-400 V8's (1958-1986).