The Hydrolevel 48-3203SF Hydrostat is a part likely used in a boiler system. Hydrostats are control devices that regulate the temperature of the water in a boiler. They are essential components in maintaining a comfortable and efficient heating system. This particular model, the 48-3203SF, may have specific features or be designed for particular applications within a boiler system. ... https://www.partshnc.com/48-3203sf-hydrolevel-hydrostat