The Lennox 21W66 Induced Draft Assembly Gasket is a precision-engineered sealing component designed for use in Lennox HVAC systems, including furnaces and heating units. It ensures an airtight seal between the induced draft assembly and adjoining components, preventing air and gas leaks. This gasket enhances system efficiency, maintains proper combustion airflow, and supports safe fur... https://www.partshnc.com/induced-draft-assembly-gasket