The Fenwal 12-E27120-000-05 is a Detect-A-Fire temperature sensor designed to detect overheat or fire conditions in various applications. It's a reliable and versatile device used in fire protection systems to activate alarms. For an efficient and reliable HVAC system, the Fenwal detect a fire is a drain pan is a great choice for optimal system performance. https://www.partshnc.com/12-e27120-000-05-fenwal-detect-a-fire-225f-open-rise