Features: 1)External rotor motor 2)Big flow, high efficiency, low noise. 3)Using advanced impeller mature sheet metal forming process. 4)Impeller and external rotor motor constitute a whole, and effective in reducing device size. 5)Impeller design would comply with the theory of aerodynamics, the fans, with the advantages of high efficiency and low noise Performance Parameter: 1) Static pressure: 0Pa 2) Speed: 910/770rpm 3) Airflow: 24000/20000cbm/h 4) Power: 2000/1250W 5) Vol. / freq.: 400V / 50Hz 6) Current: 4/2.3A