The Jobe Valves Topaz Compact Valve is a float-operated valve for use in the automatic filling of water troughs, tanks and cisterns where space is limited. The compact float valve is configured for above water mounting only. The compact weighted float operates a small pilot valve, which in turn operates the main diaphragm valve. Topaz Compact float valves are positive on/off and are ideal when working with pump supplied water in a small compartment.