Overview Ultra-Seal is Mr. Gasket premium valve cover gasket material. It's manufactured from a high density cork and rubber blend to help seal minor flange irregularites and eliminate oil leakage. It creates a positive seal by controlled swelling of the gasket material when exposed to hot oil. For original equipment replacement, high performance street, drag race and oval track use. Sold as a pair. These gaskets are .187 inch thick. Fits 1960-1986 Chevrolet 262-400 Gen I Small Block Features Manufactured from high-density cork /rubber blend gasket material Creates a positive seal by controlled swelling of the gasket material when exposed to hot engine oil For OE replacement, high performance street, drag race and oval track Pack of 2 Valve Cover Gaskets .187" thick TECHNICAL SPECS Mounting Hole Quantity 4