Mr. Gasket Ultra-Seal Valve Cover Gaskets are made from a high-density and superior quality blend of cork and rubber gasket material with locating tabs. The steel core construction prevents the gasket from being drawn inside or pushed out of the engine at a high RPM. The valve cover builds a positive seal by controlling the swelling of gasket material when exposed to hot engine oil. A black latex rubber coating helps seal minor flange irregularities. Gaskets eliminate the possibility of oil leakage and are unshrinkable as well as non-sticky. Ideal for stock replacement use and are designed to suit high performance street race, drag race and oval tracks.