SAMSON Air operated 1:1 ratio double diaphragm pump constructed with aluminum chambers and equipped with Buna-N diaphragms and balls. Air motor center section features aluminum construction with a long life patented self lubricated Ekonol ring spool valve utilizing a unique stainless non-centering spring and reset button. Air inlet ball valve included with pump. Pressure ratio 1:1, Maximum free flow capacity 164 GPM (600LPM) @ 100PSI, Fluid outlet 2" NPT