The Schneider Electric (Square D) 9037HG33 Level Float Switch 2.5" NPT is a reliable liquid level control device designed for HVAC, pump, and hydronic systems. It operates by sensing fluid levels and opening or closing electrical circuits to control pumps or valves automatically. https://www.partshnc.com/9037hg33-schneider-electric-square-d-25-npt-floatswitchrightfloat