K&N has been the leader in air filter technology with their washable and serviceable drop in air intake filters. K&N invented the reusable high flow cotton air filter in 1969 and has been perfecting the technology ever since. K&N backs their filters with a K&N Million Mile Limited Warranty? to prove their drop in filters and cold air intake systems are built to last. Using the K&N air filter cleaning kit will ensure the continued performance gains and airflow are obtained down the road.