K&N Air Filter E-4552 K&N Air Filters are crafted to achieve an almost unrestricted airflow while preserving crucial filtration levels essential for the engine's longevity. The key to their effectiveness lies in the unique characteristics of the filter medium, originally developed by K&N during desert motocross racing. The air filter utilizes a high-flow cotton gauze material that is not only washable and reusable but also designed to endure the entire lifespan of a motorcycle engine. Consisting of four to six layers of cotton gauze sandwiched between two sheets of aluminum wire mesh, this media is pleated and oiled to augment its filtering capabilities and overall performance. Tailored for environments demanding maximum horsepower, enhanced acceleration, and protection against dirt and dust, K&N Air Filters significantly increase the airflow into the engine. The outcome is an air filter that is washable, reusable, and ensures engine protection throughout the life of your ride. Features: Crafted for nearly unrestricted airflow and crucial filtration levels for engine longevity Unique filter medium characteristics developed by K&N during desert motocross racing Utilizes high-flow cotton gauze material Significantly increases airflow into the engine Washable, reusable and durable