Universal Magnum Flow Round Tapered Inverted Air Filter (21-91088) by aFe. Filter Series: Pro Dry S. Flange Inside Diameter: 3.5in. Base Outside Diameter: 6in. Top Outside Diameter: 5.5in. Height: 7.5in. This high flow Pro DRY S air filters are constructed with 100Percent polyurethane on all sides and will out flow the stock paper filters for improved performance. Two layers of progressively finer synthetic media provides maximum convenience and can be cleaned with soap and water. Washable and reusable for multiple cleaning cycles, the tall, open and evenly spaced filter pleats provide excellent dust holding capacity for longer service cycle between cleanings. An integrated urethane bump seal insures a tight, leak-free seal over the life of the filter. The aFe filter system increased air flow 25Percent over the factory air filter set increasing horsepower, torque and improving throttle response.