The backdraft damper is used to prevent the backflow of lampblack or exhaust gas through air duct when the ventilation fan is off, it also prevents debris, dust and odor from entering your room. Widely used in dryers, extractors or range hoods, and other HVAC applications. You can install it in your home, kitchen, bathroom, office or living room which needs a ventilation system.SpecificationColor: White, YellowMaterial: Plastic, Metal, Aluminum FoilOuter Diameter of Interface: 80mm 100mm 120mm / 3 inch 4 inch 5 inchOverall Size: 160 x 160 mm / 6.3 x 6.3 inch (L*W)Packing List: 2 Set - 2 x Backdraft Damper with Glue*1, Screw*4, Aluminum Foil Tape*1Advantage1.
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