Manual wafer butterfly valve 1. Material:GG20,GG25 2. Medium:WOG 3. Certificate:API ... 6D,CE,TS. 4. Std:GB,DIN,BS,EN. Manual Wafer ... Iron (GG20, GG25)b. Ductile Iron (GGG50)5) Type:a. Wafer Butterfly valvesb. Lug Butterfly valves 6) Operation:a. Leverb. Gear ...