Cast Steel Swing Check Valve , Bolted Cover, Horizointal and Vertical Lines. Body : ASTM A216 WCB Bonnet : ASTM A216 WCB Seat Ring : A276-410+ STL Stem : ASTM A182-F6a Disc : ASTM A216 WCB + Cr13 Seat Ring : ASTM A105 + CR13 Valve Size : 2â , 2-1/ 2â , 3â , 4â , 6â , 8â , 10â , 12â , 14â , 16â , 18â , 20â , 24â . Working Pressure : Carbon Steel 740 p.s.i @ 100° F / 38° C