The K&N air filter has been shown to increase airflow over open induction systems in laboratory testing. Even dirty K&N filters outperform most new conventional filters. The unique K&N design decreases restriction allowing improved airflow and power. Multi-layer design allows dust and dirt to remain trapped on the outer surface of the filter while the air easily passes through. K&N air filters typically can go 30,000-50,000 miles before requiring cleaning. You would generally have to change a paper filter 3 to 5 times during this same distance. K&N air filters are actually less expensive in the long run, because they are designed for years of use and repeated cleanings. From the grueling Baja 1000 offroad race, to oval tracks around the country, to high speed Daytona and Indy racing, K&N filters are the choice of professional racers. Stock OEM replacement K&N air filters are warranted for 10 years or one million miles.