Designed to quietly ventilate grow tents, bedrooms,workplace,exhaust odors, transfer heating/cooling to rooms.The casing is made of high-quality durable plastic.Upgraded fan has low noise, low power consumption and long life by mixed flow design combined with a Pulse Width Modulated (PWM) controlled EC motor. Reinforced plastic housing and ABS blades ensure durable quality.Duct size available from 100mm to 200mm,which is 4 inch to 8 inch. Removable impeller and motor block with a terminal box.