With a polyurethane top and bottom construction, these high flow aFe Pro 5R air filter elements outperform stock paper filters. The multiple layers of progressively finer mesh cotton gauze in many of the aFe Pro 5R air filter elements give a whole new meaning to incredible airflow, providing incredible dust-holding capacity. They are also washable and reusable, making them a cost-efficient choice vs. stock paper filters. The aFe Pro 5R air filter elements are available in a variety of sizes and styles, which makes them a great choice for daily drivers who want to improve performance without sacrificing filtration. These air filter elements are also suitable for both street and track use where maximizing performance is a main priority.