Royal Purple Max-Clean is a state-of-the-art high performance fuel system cleaner that maximizes the performance of your fuel system. Max-Clean restores fuel economy by deeply penetrating deposits and cleaning injectors, carburetors, intake valves and combustion chambers. Royal Purple Max-Clean is EPA / CARB Compliant. Recommended for use in gasoline and diesel engines and can be used with all ethanol blends or biofuel. Max-Clean can be used in both 4-cycle & 2-cycle engines and will not harm vehicle emissions equipment.