... assurance 2.Standard:ISO, ANSI,API,BS,DIN,JIS Cast Iron Manual Wafer Butterfly Valve Handle Butterfly is installed in petroleum ... textile,paper making,hydropower, marine, urban water supply and drainage, metallurgy,energy and other system which media is corrosive, non-corrosive ... , compact, lightweight, easy to assemble and repair.2.low operating torque,open and shut quickly just turn 90degree.3.Low ...