The Rheem-Ruud AS-59066-89 Stainless Steel Heat Exchanger Assembly is a durable replacement component designed for compatible Rheem and Ruud gas furnaces and heating HVAC systems. It transfers heat from the combustion process to the circulating air while keeping combustion gases separated from the indoor airflow for safe operation. Constructed from stainless steel for enhanced durabil... https://www.partshnc.com/ss-heat-exchanger-assembly