1.) Charging valve. 2.) Refrigerant R12, R22, R502, R134a & R407c. 3.) Smooth Surface, no defects. Charging ValveTechnical Performance ItemAB/ ... .0MPa,resisting pressure 4.5MPa. Suitable refrigerant R12, R22, R502, R134a and R407c.Suitable temperature -40° ~ +120°.Surface should be smooth ...