... different standards 5.handle,hand wheel,electric,pneumatic Rubber Lined Wafer Type Butterfly ValveFeatures:1. Small in size, light ... thousands opening/closing operations.6. BUbbles-tight sealing with no leakage ubder the pressure test.7. Wide ... Oils, Acids,Alkalis, etc.Operating mode manual, worm gear, pneumatic, electric, etc. Standard: Design & ManufactureFlange ConnectionFace to Face DimensionTest ...