neverest® RKI 4" Inline Backdraft Damper, One-Way Airflow Check Valve for Ducting – Spring Loaded Shutter with Airtight Rubber Seal – Prevents Drafts for Dryer Vents, Bathroom & Range Hoods

neverest® RKI 4" Inline Backdraft Damper, One-Way Airflow Check Valve for Ducting – Spring Loaded Shutter with Airtight Rubber Seal – Prevents Drafts for Dryer Vents, Bathroom & Range Hoods

• ONE-WAY AIRFLOW CONTROL: This passive inline check valve allows air to exit while automatically blocking outside air from entering. Perfect for stopping cold drafts, odors, and backflow in your home’s 4-inch ventilation ducts.
• AIRTIGHT GASKET SEAL: Features a high-quality internal rubber gasket and foam padding. Unlike standard dampers, the RKI ensures a tight seal to maximize energy efficiency and prevent annoying "whistling" noises from air leakage.
• REINFORCED SPRING-LOADED BLADES: Equipped with a strong internal spring that keeps the aluminum flaps closed when not in use. The shutter opens smoothly under pressure from your exhaust fan and snaps shut instantly when airflow stops.
• SILENT OPERATION: Designed with noise-dampening foam strips to prevent the aluminum blades from rattling or clanging against the housing. Enjoy quiet ventilation even in windy conditions or high-pressure systems.
• EASY INLINE INSTALLATION: The galvanized steel housing fits snugly inside any standard 4-inch (100mm) circular duct. Ideal for upgrading existing dryer vents, kitchen range hoods, bathroom fans, and HVAC systems.