Everbilt 4 in. Draft Blocker

This 4 in. Draft Blocker helps to prevent cold air from entering the home through the vent. The flap opens when the dryer or fan is operating to allow the air and lint to exhaust. The flap remains closed when the dryer or fan is turned off.

• Ideal for use with dryer, kitchen, and bath fan venting
• Features a one-way direction air flow design
• Prevents cold air from entering the duct system