Vortex Float valves are float operated valves for use in filling water storage tanks. Th Valve is configured for above water mounting only. The Float operates a small pilt valve that in turn operates the main diaphragm valve. Vortex Valves are a good choice where maximum flow, compact, robust, non-corrosive construction and variable float levels are desired. Vortex Valves are available in 3 sizes (1.25" , 1.5", and 2"). operating pressure is 5-100 psi, with flow rates up to 300 gpm. NSF 372 Certified for potable water systems. Valve has a lock off switch to close the valve manually.