The Laars Heating Systems E2366700 Immersion Well is a protective sensing component designed for 3/16-inch bulb temperature sensors. Installed in Laars boilers and hydronic heating equipment, it allows the sensor bulb to monitor water temperature while keeping the sensing element protected from direct contact with system fluid. Its durable stainless-steel sheath and secure set-screw d... https://www.partshnc.com/laars-heating-systems-e2366700-immersion-well-3-16-bulb