Comparison : Item # R398, High Flow Regulator
Item # R398G, High Flow Regulator with Gauge (0 to 160 psi)
Item # R398H, High Flow Regulator with High Pressure (10 to 250 psi Adjustment)
Item # R398L, High Flow Regulator with Instrument Pressure (3 to 20 psi Adjustment)
Item # R398P, High Flow Regulator with Low Pressure (3 to 60 psi Adjustment)