... Wafter 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 ... .Top Flange: ISO5211Face to Face: API609, ISO5752 series 20, BS5155Test&Check: API598 Wafer Type Check Valve