... B16.5: WELDING NECK FLANGE, SLIP-ON FLANGE, BLIND FLANGE, HIGH HUB BLIND FLANGE, SOCKET WELD FLANGE. LAPJOINT FLANGE, THREADED FLANGE ... , 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, 15000Psi, 20000Psi, 25000Psi ...