Seal-4-Good multi-layer aluminum flange gasketSeal-4-Good Ford SB 221-302-351W oval 1.5 x 1.125inLimited Lifetime Replacement WarrantyMade Of Dead Soft AluminumMulti Layered Which Conforms To Header FlangesCreates Ultimate SealWill Not Blow-Out Or Burn-OutThe Percy's Seal-4-Good Reusable Flange Gaskets are multi-layered and made from a special "Dead Soft" Aluminum, which conforms to header flanges for the ultimate seal. Since the Seal-4-Good is made from multiple layers of dead soft metal, it easily conforms to small imperfections that a copper gasket simply can not. Due to this construction, these gaskets will not blow out or burn out when properly installed.Flange gasket