Uniweld RHT8013 Medium/Heavy Duty Two Stage CO2 Regulator with CGA320 Inlet Two tri-layered reinforced neoprene diaphragms. (1st stage at 1-5/8 inches, 2nd stage at 2 inches) CGA320 Inlet, Maximum Inlet:3000 PSIG Large Brass T-handle for Smooth, Accurate Adjustments Externally serviceable reseating pressure relief device (PRD). PRD not designed to protect downstream equipment Delivery pressure: 5-125 PSIG