K&N Universal Round Tapered Filter Wrap - Black - 6in Base ID x 4.625in Top ID x 9in Height 1999-lexus-gs400-esi4423656 Honda made it clear that

Honda made it clear that the FK8 and subsequent FL5 are designed for speed

Single catch can kit for the Mitsubishi Evo 8/9

The K20C1 is quite the powerhouse in the Civic

HKS GT2 S/C SYSTEM Pro 16-18 Mazda MX-5 SKYACTIV-G 2

which utilizes the FK8

K&N Universal Round Tapered Filter Wrap - Black - 6in Base ID x 4.625in Top ID x 9in Height 1999-lexus-gs400-esi4423656 Honda made it clear thatThe K&N PreCharger filter wrap is specially designed to extend the service interval of your K&N Filtercharger filter when used in very dusty conditions. They are made from durable polyester material containing a uniform weave. The PreCharger will stop small dirt particles with minimal restriction to the airflow of the filter.