Patented Pro-GUARD 7 Media: Filter features oiled Five-Layer Progressively finer mesh cotton media with Two-layer Progressively finer porosity synthetic media for high filtration efficiency in extreme dirty environments Rounded Open Pleats: Design provides more usable filter surface area for increased airflow and greater dust holding capacity 100% polyurethane construction: Durable material allows multiple cleaning cycles and excellent sealing capacity without foam gaskets or sealing grease Washable and reusable: Designed for extreme environments, the media can be washed and reused for multiple cleaning cycles OE replacement performance filters: Will not void the factory warranty and are emission legal in all 50 States