The 4 gravity shutter from zexum is an unobtrusive ventilation accessory designed to prevent backdraught by connecting to an exterior wall. Featuring 5 lightweight shutter fins, this product allows air through, but protects from backdraught, ingress of water, and small animals. Constructed from durable non-corroding weatherproof ABS, this vent simply does the job without worry of regular maintenance or failure, and is available in brown or white colouring to ensure a subtle blend with your building. Main Features: 4 inch circular spigot for vent connection via pre-made screw holes ABS plastic construction provides durable and non corrosive functionality 5-fin shutter reduces ingress of water and small animals Lightweight fins allow air to pass out easily Available in brown or white Technical Specification: Grille Dimensions: 150mm x 150mm Spigot: 4 Inch / 100mm Product Material: ABS Plastic No. of Shutter fins: 5 Note: Images are for illustrative purposes only, small variations to colour and shape may occur