GReddy S Type 1.3 bar Radiator Cap SpecificationsThis GReddy S Type 1.3 bar radiator cap is compatible with many OE radiators with standard caps and fits most Nissan Subaru Mazda and some Toyota Mitsubishi and Honda vehicles.Why use a 1.3 bar cap? A radiator cap rated at 1.3 bar will open later than an original cap usually rated at 0.9 or 1.0 bar thereby increasing the pressure in your cooling system. It increases the boiling point and ensures a more efficient cooling system for heavy duty use.