Repa Market 4" Inch / 100 mm Duct Backdraft Blockers Pipe Connector with Backdraught Shutter Backflow Preventer Dryer Vent Adapter Inline Air Extractor Line Coupler Valve

PRECISE DIMENSIONS: Insertion diameter: 3.89 inch / 99 mm Insertion depth: 1.18 inch / 30 mm Total width: 2.4 inch / 62 mm., this product offers easy do-it-yourself installation, ensuring hassle-free compatibility with your ventilation system. EFFICIENT VENTILATION: Engineered for reliable airflow control in bathrooms, kitchens, cooker hoods, and inline extraction setups — helps prevent cold drafts, odors, and outside air from entering through your dryer vent or duct system. ADVANCED BACKFLOW PROTECTION: Equipped with a pre-installed balanced damper that effectively stops unwanted odors, noises, and drafts from backflowing through your duct system. OPTIMIZED FOR MULTI-SECTION DUCTING: A critical airflow safeguard for long or multi-section ductwork, ensuring stable performance in ventilation, passive stack venting, air conditioning, positive-pressure systems, tumble dryer setups, HVAC installations, and air heating networks. DURABLE MALE-SPIGOT DESIGN: Constructed with a male spigot and durable white plastic housing, ensuring long-lasting performance in extractor fan systems.