Technical Specification 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