HKS 15009-AK004 D1 Limited Edition Radiator Cap
HKS High Pressure Radiator Cap Limited Race Edition for most of Mazda, Mitsubishi, Nissan, Subaru's vehicles. In a cooling system, a higher pressure equates to a higher boiling point for the coolant. Higher coolant pressures also transfer heat from the cylinder heads more efficiently. A radiator cap with the high pressure rating that the radiator is designed to accept.