Designed to increase horsepower and acceleration while providing excellent filtration. K&N air filters use a four-layer cotton gauze filter membrane with a large surface area to improve airflow and offer longer service intervals. K&N air filters feature an epoxy-coated aluminum wire mesh incorporated into the back-fire screen to protect the filter element. K&N air filters are washable and reusable. Simple drop-in performance. Lifetime air filter with K&N Million Mile Limited Warranty®. The world's best air filter. Filter Specifications: Product style: Unique air filters. Filter material: Cotton gauze. Flanges: None. Height: 2.25 inches (57 mm). Filter re-oiling amount: 0.28 ounce (8 ml). Outside length: 5.75 inches (146 mm). Outside width: 4 inches (102 mm). Weight: 0.81 pound (0.37 kg).