Description

Active Air's ACBD4 4-inch backdraft damper is an in-line, one way air flow valve that requires minimal pressure to operate and has no moving parts. Tested to UL 723 standards, this non-restrictive damper gives you the full force of your fan which installs easily and fits snugly inside the duct. Made of galvanized steel, the backdraft damper prevents air leakage into your fan setup and back drafts of air when the fans are switched off.