4" Backdraft Damper

This upgraded 4-inch backdraft damper features a reinforced 0.6 mm design with new inward pressure ribs for extra durability. Made of galvanized steel with an aluminum axis and a carbon steel spring, it’s built to last. The damper fits 100 mm ducts and should be installed horizontally for smooth operation. Suitable for use in dryer vents, range hoods, bathroom fans, kitchen vents, and other HVAC systems, it automatically opens with airflow and closes tightly when air reverses. A rubber seal ensures a complete, quiet closure to prevent backflow.