Aluminium Alloy Round Air Vent Louver Home Hardware 37mm Dia 10 Pcs Product Name : Air Vent;Design : Mesh Hole, Round Shape Color : Silver Tone;Material : Aluminium Alloy Each Hole Diameter : 2.5mm / 0.1";Upper Diameter : 37mm / 1.5" Bottom Diameter : 24mm / 1";Thickness : 9mm / 3.5" Net Weight : 47g;Package : 10 x Air Vents