K&:N universal air filters variable in connection diameter are supplied including adapter rings with which the connection diameter can be varied in 3 sizes. The flange of these filters is made of ultra-strong flexible rubber which absorbs vibrations excellently and ensures a safe and sound mounting. K&:N universal air filters are washable and reusable. Specifications: Product type: Round conical universal air filter Design: Round conical Base plate diameter: 4.5 inches (114 mm) Diameter top plate: 3.5 inch (89 mm) Connection diameter: 2.75 inch (70 mm) Connection diameter 2: 2.5 inch (64 mm) Connection diameter 3: 2.25 inch (57 mm) Flange Length: 1.125 inch (29 mm) Flange type: Centered Height: 4.5 inches (114 mm) Filter material: Cotton Material: Metal / Rubber Finish: Chrome Color red Guarantee : 2 years