Cleans fuel injectors and carburetors. Prevents future deposit build up. Increases your engine's performance and increases your fuel mileage by increasing your fuel economy, lost horsepower, hesitation, and rough idling. Will not harm oxygen sensors, catalytic converters, hoses, fuel lines, or fuel level sensors. Not recommended for diesel engines, 2 stroke, or flex-fuel engines. 1 bottle treats up to 21 gallon and can be used at every fill up.