aFe MagnumFLOW Air Filters Round Racing P5R A/F RR P5R 11 OD x 9.25 ID x 5 H E/MaFe MagnumFLOW Air Filters Round Racing P5R A F RR P5R 11 OD x 9. 25 ID x 5 H E M Constructed with 100 percent polyurethane on top and bottom, this high flow, oiled performance filter is our highest flowing filter media. Five layers of progressively finer mesh cotton gauze media provide maximum airflow for best performance results. Washable and reusable for multiple cleaning cycles, the tall open evenly spaced pleats provide excellent dust holding