K&N Replacement Air Filter Monster S2R / S4R SIZE_4L Nylon fabric composite material

Nylon fabric composite material

Underbelly ties for a secure fit

Drills up to a 2mm hole (requires 2mm drill bit or smaller - not included)

Allows for easy removal and installation of standard valve cores in tubed or tubeless valve stems (Schrader valve)

Spring Diameter: 9mm

K&N Replacement Air Filter Monster S2R / S4R SIZE_4L Nylon fabric composite materialThis K&N racing air filter has just two layers of cotton to provide even lower air restriction than our replacement air filter for street vehicles. Unlike K&N replacement air filters, fuel management modifications will be necessary with this racing filter. K&N racing air filters are washable and reusable. Features: Designed to increase horsepower and acceleration. Designed for racing and track applications, not for street use. Washable and reusable