AC Infinity 4-Inch Backdraft Damper Duct Insert

The AC Infinity AC-BDD4-B fits inside 4-inch rigid or flexible ducting and opens under low air pressure from an inline fan or extractor. When airflow stops, its spring-assisted aluminium butterfly blades close automatically to help prevent backflow.

Two outer rubber gasket rings create a secure friction seal against the inside of the duct. This keeps the damper firmly positioned in horizontal or vertical installations without requiring additional fasteners.

Key Features

• One-way airflow control: Helps block cold outdoor air, odours, pests, wind and unfiltered air from travelling back through the duct.
• Low-resistance butterfly blades: Lightweight aluminium shutters open with minimal fan pressure to help maintain airflow.
• Automatic closure: Spring-assisted blades close when positive airflow stops.
• Dual rubber gasket rings: Create a tight friction seal around the housing and help prevent air leakage.
• Durable steel chassis: Powder-coated galvanised steel offers resistance to moisture and elevated HVAC temperatures.
• Flexible installation: Suitable for horizontal or vertical mounting inside compatible ducting.

Technical Specifications

Suitable Applications

• Kitchen and bathroom extraction: Helps prevent outdoor draughts and odours entering through range hood, bathroom fan and tumble dryer vents.
• Indoor cultivation ventilation: Helps maintain sealed grow-room conditions when fans are idle and reduces unfiltered air intrusion.
• HVAC and appliance venting: Helps limit downdraughts in compatible residential ventilation and exhaust systems.