... Disc: 65 - 45 - 12, WCB, 316, Aluminum bronze Seat: EPDM, NBR, Viton Main Performances Nominal Pressure(lb): 50, 150 Nominal Diameter ... API: 598 Suitable Media: Water, oil, gas, corrosive material EPDM/NBR seat: -84.2 176 (º F) or - 64 5 80 Viton ...