This is the HTFC cabinet centrifugal ventilation fan produced by Quanda. It is a box-type centrifugal fan with high-efficiency and low noise. According to different installation configurations, the fan could provide customers with 12 different angels’ of air inlet and outlet positions. In addition, considering the requirements of performance regulation for different operating points, a dual speed motor is utilized so the exhaust fan realizes two-gear speed regulation. Currently, this product is widely applied in office-buildings, theaters, factories, malls and hospitals using compatible air treatment and purification products.