Fel-Pro1604 Small Block Valve Cover Gaskets are made from durable quality of cork/rubber with steel core material. An excellent choice for engines, especially those that produce high horsepower. Deliver reliable sealing under grueling racing conditions. Extra-thick seals yield better compressibility for tough applications. Longer life, good sealing characteristics without leak paths. The extra-thick seals yield better compressibility for tough applications. They have a metal core for extra strength, with a special cork-and-rubber compound bonded to both sides. The gaskets use cork particles evenly distributed throughout a rubber binder resulting in a compressible gasket without leak paths. Thickness : 0.313 inch. Fits to Chevrolet. Comes in a pair.