Upgraded Backdraft Damper Design: This 4 inch damper by Hon&Guan features reinforced concave inward pressure ribs and a 0.6mm thick galvanized steel body—stronger, more durable, and built to last.Multi-Material Construction: Crafted for precision and reliability, it uses galvanized steel for the housing, aluminum shafts, and carbon steel springs to ensure high performance in ventilation systems.Effective One-Way Airflow Control: Valve wings open with airflow and auto-close quietly when flow reverses, preventing air backflow in ventilation fans, dryers, kitchen hoods, and HVAC ducts.Versatile HVAC Compatibility: Ideal for ducting systems with both flexible and rigid pipes. Compatible with dryer vent backflow preventers, bathroom fans, kitchen exhaust, and general ventilation setups.Simple, Quiet Installation: 100mm diameter and 88mm length, with a rubber ring for airtight sealing and noise reduction. For best performance, install horizontally with the spring aligned with the airflow.
