... Butterfly Check Valve DN50-800mm PN(MPa): 1.0/1.6 API,ANSI,ASTM,DIN,BS,JIS approved wafer type double disc ... butterfly check valveFeatures:1)Working temperature: -25*C~120*C2)Applicable medium: Fresh water, sewage, sea water, air ... to Face: API609, ISO5752 series 20, BS5155Test&Check: API598 Wafer Type Check Valve