Driven Racing Oil Carb Defender, Formulated to protect against Ethanol corrosion and induction depoits caused by Ethanol-blended pump gasoline and the moisture it attracts. Additives control combustion chamber residue. They also clean and protect surfaces of the fuel systemand intake tract.. Carb Defender acts as a fuel stabilizer that extends fuel storage life. 10 oz Bottle treats up to 25 gallons