API gate valve Body :A216 WCB Bonnet :A216 WCB Stem: A182 F6a Stud :A193 B7 Nut :A194 2H Yoke: A216 WCB Back seat: A182 F6a Pack bushing :A276 410 Pack plate :A216 WCB 1.All of valve part material comply with ASTM standard. 2.Above material is our normal one.If client has special requirment for it, we can choose material as per detailed site condition.