EC radial duct fan for direct installation in the duct system. Housing made of galvanized sheet steel with round connection pieces adapted to standard ducts. Radial impeller with backwards curved plastic blades. Pressed directly onto the motor and dynamically balanced as a unit. Low noise, high efficiency. Energy-saving, speed-controlled EC external rotor motor with protection class IP 44. Maintenance-free, free from radio interference and ball bearings. Integrated electronic temperature monitoring for EC motor and electronics. Stepless speed control with potentiometer or stepless speed regulation with universal control system. Connection via standard terminal box (IP54) on the outside of the housing.