Backdraft Damper HVAC Inline Fan Vent Deflector（One-Way Airflow Ducting Insert Backflow Preventer Duct Draft Blocker）
Size:4 Inch
- 【Material】The 4 inch 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.
- 【Installation method】The position of the spring should be horizontal for horizontal installations so that it can open and close optimally
- 【Wide applications】Back draught valves can be inserted into ventilation ducts which are flexible or non-flexible. Designed for use with range hoods, bathroom fans, kitchen and other home HVAC applications.
- 【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.
- 【Backdraft Shutter】Hon&Guan Draft Blocker designed to improve ventilation by preventing air from re-circulating when the fans are not in use, rubber ring ensure 100% closure and quiet closing.
