Improves airflow for better performance and accelerationOil-free for easy quick servicing and yet washable/reuseable air filter for long service life with life-time warrantyPro DRY S Three-Layer Progressively finer porosity synthetic media for high airflow with high filtration efficiency.Tall, Rounded, evenly-spaced pleats for maximum dust holding capactiyConstructed with 100% pliable polyurethane for great seal without use of foam gaskets or sealing grease.