1:Swivel Ring Flange 2:1/4" --- 72" 3:150#,300#-- ... Steel 5:Marking as Customer design. Carbon Steel Swivel Ring Flange Type Weld Neck,Slip-On,Blind,Socket Weld,Lap ... Joint,Threaded,Orifice Flange,Swivel Flange,Spectacle Blind,Etc. Size 1/2"-72"Class 150#,300#,400#,600#,900 ... HUB BLIND FLANGE, SOCKET WELD FLANGE.LAPJOINT FLANGE, THREADED FLANGE. RING TYPE JOINT FLANGE.Pressure Class : 150, 300, 400 , 600 ...