... 400 , 600 , 900* ASME/ANSI B16.36 : (ORIFICE FLANGES) WELDING NECK FLANGE, SLIPON FLANGE, THREADED FLANGE.Pressure Class : 300, 400 , 600 ... 150, 300, 400 , 600 , 900,1500, 2500* MSS SP44 : WELDING NECK FLANGE, BLIND FLANGE.Pressure Class :300, 400 , 600 , 900* ... API 6A : WELDING NECK FLANGE, THREAD FLANGE,BLIND FLANGE.Pressure : 2000Psi, 3000Psi, 5000Psi, 10000Psi ...