Hand Operated Drum Pump Max Outlet Pressure 7 psi Pump Connection OD 3/8 in Features External Pressure Release Valve Must be Opened by Hand Before Removing Pump from Container Groundable Pump Internal Pressure Relieve Valve Opens Automatically If Container Pressure Exceeds 6Psig Standard Pump Internal Pressure Relieve Valve Opens Automatically If Container Pressure Exceeds 8Psig Housing Material - Pumps Polypropylene