DWT-II glass centrifugal roof ventilator can be used to pressure for higher places. Its base, impeller, hood, are made of high quality glass fiber reinforced plastic composite materials produced. For industrial and mining enterprises, workshops, warehouses, stadiums, theaters, power plants, laboratories, rubber factory, car factory, a motorcycle factory and textile, metallurgical and other places used for ventilation. This series of fans are handsome in appearance, compact structure, high strength, light weight, corrosion resistance, aging resistance, power consumption, low noise, reliable operation, economical and practical, easy installation and maintenance and so on. It does not allow the transmission of gas with viscous material, contained in the dust and hard particles ≤ 150mg/m3, gas temperature ≤ 60 ℃, relative humidity ≤ 100%.