[ABS Material]-- The air vent adopts quality ABS, long lasting, and strong ability to withstand gravity, environment friendly no smells and non-toxic [Built-in Fly Screen]-- There's a removable plastic grid/screen to block, bigger things can't get in your house, providing you a better healthy life [Enjoy Odor-Free Environment]— Circular mesh can make the wind easily flow into the spaces where you are staying, it will giving you a fresh and odorless life and work environment [Easy to Install]— Bottom diameter 182mm (7.16 Inch), the same diameter hole can be mounted directly, and fits snugly in the duct using the friction from the black plastic wings [Wide Range of Applications]— Applicable to kitchen, bathroom, office, meeting rooms, ect. Also compatible with a 8 inch inline fan system FOCCTS 8 Inch Round Air Vent ABS Louver Grille Cover White Soffit Vent with Built-in Fly Screen Mesh for Bathroom Office Kitchen Ventilation Feature Built in fly screen mesh: it helps to give you a better healthy life. Premium material: new high quality ABS was adopt, environment friendly and non-toxic. Easy to use: the white panel can be freely detached, very convenient to clean and maintain. Portable and Lightweight: available for wall mounted or ceiling mounted. Diameter of 4 Inch, stylish design, ideal for room exhaust and ventilation use. Specification Material: ABS Size: Bottom Diameter :7.16 inch Delivery 1 x ABS Mesh Hole Louver