The Schneider Electric (Square D) 9037HG30 Close/Rise Float Switch 50 PSI Max is a dependable liquid level control device designed for HVAC, pump, and hydronic systems. It functions by closing the electrical circuit as liquid levels rise, activating pumps or valves to maintain proper fluid control. https://www.partshnc.com/9037hg30-schneider-electric-square-d-floatswitch-50max-closerise