KN replacement filters are designed for all motorcycles and ATVs to O.E.M. (manufacturer) size specifications and fit into your original O.E.M. air box without modification or jet changes. Due to design and unique high flow characteristics, KN filters allow engines to breathe free and produce optimum horsepower. Under most conditions KN air filters never need to be replaced - with proper cleaning and care, KN air filters will last the life of your engine. Designed to increase horsepower and acceleration while providing excellent filtration. KN air filters use a four-layer cotton gauze filter membrane with a large surface area to improve air flow and offer longer service intervals. KN air filters feature an epoxy-coated aluminum wire mesh incorporated into the back-fire screen to protect the filter element. KN air filters are washable and reusable. Lifetime air filter with KN Million Mile Limited Warranty. Simple drop-in performance. The worlds best air filter. Filter Specifications: Product style: Round straight universal air filter. Filter material: Cotton gauze. Flange inside diameter: 2.375 inches (60 mm). Flange length: 0.75 inches (19 mm). Flanges: 1. Flange type: Centered. Height: 6.063 inches (154 mm). Outside diameter: 4.438 inches (113 mm). Top material / finish: None. Top style: Rubber. Filter re-oiling amount: 1.42 ounces (42 ml). Weight: 0.95 pounds (0.43 kg).