DNA Motoring AF2351201 Intake Air Filter (2.5" Inlet) Filter consisted of 2 layers to double the filtration efficiency. Improves up to 95% filtration efficiency. Micro cotton gauze type filter material, washable and reusable. For intake or turbo usages. Overall dimension: 6.25" (Length) x 6.25" (Diameter) / 2.5" filter outlet