| Pre-wired internal box for easy installation | UL listed and CSA certified | Housing constructed of heavy gauge sheet metal with baked enamel finish | 100% speed controllable | Suitable for airstream temperatures up to 140 F | Ebm-papst external rotor motorized impeller for excellent heat dissipation, even at low RPM | Backward curved impeller featuring a well designed venturi for maximum performance | Permanently lubricated sealed bearings for maintenance free operation | Motor equipped with automatic reset thermal overload protection | Statically and dynamically balanced as one integral unit to provide vibration free performance | HVI certified and tested | 5 Year Warranty | Exterior-mounted Centrifugal Fan for wall and roof application.