A six step maintenance system was designed to service your K&N air filter element. With these kits you can completely clean and restore air flow efficiency so your filter performs like new. Each kit contains one squeeze bottle of filter cleaner and one 6 1/2 ounce aerosol can or 12 fluid ounce squeeze bottle of filter oil. Use one of these recharger kits on a regular basis and you may never have to buy another filter again.