Brown Gravity Grille 183mm External Dimension with 150mm 6 inch Round Rear Spigot and NotReturn Shutters Ducting Air Vent

Brown Plastic Ducting Air Inlet / Air Outlet with Gravity Shutters. 183mm x 183mm external dimension with 6 inch / 150mm round male rear spigot on the back of the grille for indoor or outdoor use. Non-return shutter flaps close automatically when not in use. Stops unpleasant odours, noises, or draughts flowing back through your duct. Gravity flap - no need for springs that could break. Easy to install, just push-fit duct and fittings together. Perfectly suited Bathroom or Kitchen extractor fan, Hydroponics fan, or In-Line Extract Fan. This grille can be used as a part of a long ductwork run for a variety of purposes including whole house ventilation, passive ventilation, positive input, air conditioning, HVAC, and Heat Recovery Systems. Suitable to use in compliance with Part F Building Regulations. Airflow performance independently tested by BSRIA or BRE. Free Air: 16,000mm2. Static Pressure Drop in Pascals: 15 l/s = 6.91 Pa - 30 l/s = 8.76 Pa - 60 l/s = 11.10 Pa.