... basis of original axial flow roof fan, this series fan adopted the international newly developed product, fan NO:3'-11',airflow:1450- ... strenth, long life and good stability. Thermometer: made of FRP,flexible to open and closed, ventilate well Bird-prevent Net: adopt ... Motor: adopt low-noise and waterproof motor, rotate steadily.This fan matched steepless speed governing motor, be made of excellent FRP ...