Description:1. ABS plastic have a good hardness and it is extremely lightweight.2. It also have a good resistance of acid and alkali.3. A design with thinner top and thicker bottom can make this vent much convenient to connect.4. Internal arc design reduces wind resistance.5.Widely used on bathroom or kitchen extractor fan, In-line extract fans or cooker hoodSpecification:Material: ABS PlasticTop Outer Diameter: 75mm / 2.95 InchBottom Outer Diameter: 100mm / 3.94 InchHeight: 45mm / 1.77 InchMounting Hole Centre Distance: 75mm / 2.95 InchApprox Weight: 163gPackage Content:5 x Duct Connector