Mr. Gasket Copper Seal Exhaust Gasket is made from long lasting 0.043" solid copper which will not shrink, deteriorate, or blow out. It provides excellent sealing performance, load retention, chemical resistance, structural strength and durability. It is manufactured from high-temperature acrylic blend exhaust material and can be trimmed if necessary for modified ports. It suits OE replacement, high performance street, drag race and oval track. The exhaust ports on the gasket feature embossed O-ring, designed to increase sealing pressure around each exhaust port to create a tight, leak-proof seal between the cylinder head and the exhaust manifold or header. They are also ideal for tow vehicles and motor homes. It fits FE stock port, 8 bolts.