Round series of duct heaters available in 6", 8" and 10" diameters. Zero Clearance Approved. Flex duct can be mounted directly to unit (250°F / 121°C rated), no transition or extra metal duct required. Factory installed airflow switch and probe, no need to specify right or left airflow, superior design allows for operation in either direction. Widest range of KW offering in the marketplace. Single Point Power Connection.