... , low Leakage. 3.Easy to implement remote control. Two Way Pneumatic Water Flow Control Valve Main Technical Parameters DN(mm)1520253240506580100125150200250300350400450500600Ball core ... , 304,304L,316,316L,corrosion-resisting alloy…lTight seal surface materials:hard chromium plating,surfacingNI60,Hard alloy spray welding,Spray welding ...