Structure formation: bolt-jointed bonnet outside stem yoke structure Driving manner: Hand operated Design standard: ASME B16.34,BS 1873 Body: ASTM A216-WCB,ASTM A217-WC1\WC6\WC9\C5 ASTM A351-CF8,CF8M,CF8C,CF3,CF3M Disc: ASTM A 182 GR.F6A,ASTM A 182 F22, ASTM A182-F304,F316,F321,F304L,F316L Stem: ASTM A 182 GR.F6A,ASTM A 182 F22, ASTM A182-F304,F316,F321,F304L,F316L Packing: graphite gasket: graphite or stainless steel bonnet: ASTM A216 WCB ASTM A217-WC1\WC6\WC9\C5