HKS 1.0mm Thick Metal Head Gasket | Subaru BRZ / Scion FR-S (13-21) (23001-AT004)HKS Metal Head Gasket SC 1. 0mm Thick Opposed Bead Stopper Type Metal Gasket for the FA20 engine of 86 BRZ provides higher bore sealing durability than a stock gasket. Stopper structure of the bore seal is separated type so it prevents leakage even under high gas pressure at high engine output. A high pressure seal is formed around the combustion chamber through the use of stoppers which create a step within the gasket for optimum sealing. By making