aFe ProHDuty Air Filters OER P5R A/F HD P5R RC: 12-3/4OD x 8-3/8ID x 27HaFe ProHDuty Air Filters OER P5R A F HD P5R RC: 12 3 4OD x 8 3 8ID x 27H With five layers of progressively finer mesh cotton gauze media between 100 percent polyurethane top and base, the aFe Pro 5R heavy duty oiled conical performance filter provides excellent airflow for maximum horsepower and torque. Washable and reusable for multiple cleanings, the tall, open, evenly spaced pleats provide excellent dust holding capacity for longer service cycle