Airvent 401903 100mm (4") White External Gravity Shutter Vent Grille - 4821W

Prevent cold backdraughts and protect your ducting with the Airvent 100mm White Gravity Grille (401903 / 4821W). Designed for external wall mounting, this durable ABS plastic shutter features lightweight gravity-operated louvres that open automatically when your fan is running and close tight when turned off to stop wind, rain, and drafts. Compatible with standard 100mm (4-inch) round flexible or rigid ducting, it provides an ideal finishing outlet for bathroom extractor fans, kitchen hoods, and tumble dryer ventilation. Key Features: Automatic Backdraught Protection: Gravity louvres open during airflow and seal shut when idle. Universal 100mm Fit: Connects seamlessly to standard 100mm (4") circular ductwork. Durable ABS Plastic: Weatherproof and UV-resistant material built for continuous outdoor use. Easy DIY Installation: Surface-mount screw-fix design for fast fitting into external walls.