TEGIWA Thermal Gasket. This gasket helps reduce intake air temps by removing the direct connection of the intake manifold to the cylinder head. By placing this thermal shield between the intake manifold and the cylinder head, you will help reduce the amount of heat soak the intake manifold normally absorbs from the cylinder head resulting in an increase in power. Made from PTFE - the ultimate thermo-plastic and manufactured in the UK using the latest water-cutting technologly. This will fit all inlet manifolds, OEM, Skunk2 etc. Suitable for all 4G63 engines from 96-08.