Chevy SBC 350 1955-85 Rubber w/Steel Core Valve Cover Gasket Set - Black They feature greater strength and

They feature greater strength and durability

Design improvements to the splines

Constructed from a composite material with a steel core

Made from 5051 aircraft aluminum alloy

these caps have a one way valve

Chevy SBC 350 1955-85 Rubber w/Steel Core Valve Cover Gasket Set - Black They feature greater strength andSpeedmaster valve cover gaskets are manufactured from high quality rubber, which is molded over and vulcanized to a rigid steel frame. They won't leak, blow out, or get sucked in, the way stock or inferior quality aftermarket gaskets can. These gaskets feature superior quality rubber and steel, which outlast cork and rubber composite designs to provide years of dependable service, especially if you frequently have to remove and reinstall the valve