Hon&Guan 4 Inch Inline Booster Duct Fan with Speed Controller and 4 Inch Backdraft Damper

Upgrade design The 4 inch damper on both sides of the top and bottom of the two new concave inward pressure rib, and increase the thickness to 0.6mm,to ensure that the product is more solid, not easy to damage., Material The backdraft damper and the flap leaves is made of a galvanized steel, the axis are made of aluminum, while the spring are made of carbon steel., Lightweight valve wings The valve wings open under the pressure created by the airflow; when the air flows in the opposite direction, it is automatically closed under the action of the spring, so as to cut off the flow. Rubber ring ensure 100% closure and quiet closing., Energy-Efficient Ventilation This powerful inline duct fan speed of 4500 RPM can create the air flow of 130 CFM, Maximum power consumption is only 6W. Upgrade DC motor & low noise effectively circulating air, quickly move vast amount of air to exhaust odors., Adjustable Controller The 4-inch duct fan includes a variable speed controller, which can allows you to adjust the airflow and noise at will.