4" Metal Backdraft Damper Backflow Preventer Draft Blocker Connector - Red
$27.99
The backdraft damper is used to prevent the backflow of smoke or exhaust gas through air duct when the ventilation fan is off, it also prevents debris, dust and odor from entering your room.
The backdraft damper is used to prevent the backflow of smoke or exhaust gas through air duct when the ventilation fan is off, it also prevents debris, dust and odor from entering your room.