Since 1969 K&N has been providing auto enthusiasts and dicerning drivers their race proven performance replacement air filters. In fact, K&N filters are the only air filters used in the Indianapolis 500.
K&N's technology came about out of the necessity for a filter that can withstand the harsh conditions of off-road racing. In off-road racing, most paper filters would get clogged up and decrease performance and throttle response. Thus came the need of a filter that could provide superior performance and not get bogged down by the high amount of dust and dirt generated in off-road racing. Where paper filters failed, the cotton gauze, aluminum mesh, and oil combination of K&N's reusable filters proved to be the competitive advantage.
K&N has designed and manufactured (in the US and the UK) air filters for over 2,400 applications, testing and retesting to ensure proper fit and performance.
By increasing airflow, not only is more horsepower made, but, depending on driving style and conditions, K&N stock replacement filters can increase fuel economy.
Not only does K&N confidently warrant their filters for one million miles against manufacturing defects, should a dealership void your vehicle's warranty because of your K&N stock replacement drop in filter, they will resolve the issue on your behalf at thier expense. That is how confident they are in their air filters.
Moreover, should a dealership blame a K&N replacement filter for any kind of malfunction, and thus void your warranty, K&N pledges to resolve the issue on your behalf at their expense.