Yamada Pumps NDP-20BSE Type, Model 851521 NDP-20 Series, Air Operated Double Diaphragm Pump, EPDM Diaphragm, EPDM Flat Check Valve / O-Rings, Stainless Steel (316) Material, 31.7 GPM Max Flow, 3/4" NPT Fluid Port, 3/8" Female NPT (includes ball valve)...