STC, 3A420-1/2, 3A420 1/2" NPT 3-Port 3-Way Double Pilot Actuated Air ValveFeatures:Port & Mounting: Body Ported.Action & Motion: Double Air Pilot, Spool Design.Operating Pressure: Valve: 0 to 115 PSI, Pilot: 40 PSI.Working Medium: 40 micron filtered air or inert gas.Valve Body Material: Anodized Aluminum.Seal Material: NBR (Buna N).Lubrication: Not Required.