This aluminum air supply diffuser is widely used in malls, office buildings, restaurants, homes, and offices, perfect for ceiling installation for low and medium-pressure intake or exhaust ventilation, air conditioning system, fresh air ventilation system. This vent cover provides horizontal air flow in 4 way for better air distribution.SpecificationExternal Size: 350 x 350mm/13.8 x 13.8 Inch(L*W)Neck Size: 225 x 225mm/8.9 x 8.9 Inch(L*W) for 9 x 9 Inch ventilation duct or canalDuct Opening Size: 300 x 300mm/12 x 12 Inch(L*W)Height: 55mm/0.2 InchColor: WhiteMaterial: Aluminum AlloyPacking List: 1 Pcs x Air Supply DiffuserAdvantageDurable Material: Made from aluminum alloy with a matte finish, this durable air supply diffuser is waterproof, moistureproof, anti-oxidation, and not easy to fade and wear. Can resist high and low temperatures.Effective Air Distribution: This air supply diffuser can supply air in 4 directions to cover the whole room, ensuring 360-degree maximum comfortable airflow with silent operation.Removable: Removable inner vanes are easy to remove, clean, and maintain,InstructionMeasure the opening, then drill screw holes on the grille, attach the air supply diffuser to the opening and fix it with screws(not included)Note: Please measure the wall opening and check the product size before purchasing.