Shurflo 5.3 GPM Pump Diaphragm 60 PSI Demand Switch 1/2" Female Ports Delivers 5.3 GPM [20.1 L/min] free flow Field-proven pump head design Driven by a 12-volt, SHURflo built sealed motor Self-priming capabilities, up to 8 feet [2.4 m] Santoprene diaphragm for chemical resistance and maximum life Viton valves provide maximum chemical resistance Automatic demand versions with built-in pressure switch, set at 60 PSI [4.14 bar] Bypass versions set at 90 psi [5.86 bar], for applications where a demand switch is not desired