PERMATEX COPPER HI-TEMP SPRAY-A-GASKET. Fast-drying, metallic copper sealant helps dissipate heat, prevents gasket burnout and improves heat transfer. Fills minor surface irregularities. Seals instantly. Fills hot spots and surface imperfections. Temperature range 50 F to 500 F. Resists all types of shop fluids, especially gasoline. Suggested applications include cylinder head gaskets and exhaust gaskets. 12 oz. aerosol can.