K&N Engineering Universal X-Stream Clamp-On Filter 4.5in Base OD x 4in Top OD x 4.031in H x 2.438in Flange ID - RX-4010

K&N XStream Top Universal Air Filters take performance to the next level with the addition of a filter within the filter's top adding more filter area for higher air flow and a longer service interval. The XStream Air Filter provides awesome air flow and outstanding filtration. When racing, in any environment, racers need all the protection and airflow they can get. K&N delivers. All K&N universal air filters are constructed with ultra-strong molded pliable rubber flanges which absorb vibration and allow for secure attachment and can also be stretched for up to 1/16 inch (1.5mm) to fit in-between sizes. K&N universal air filters are washable and reusable.