For maximum performance. Stops knocks and pings. Treats 21 gallons. Race Pro Octane Booster is formulated to stop knocking caused by low octane fuel. Special additives increase octane and clean fuel system. Race Pro Octane Booster does not contain alcohol and is safe for catalytic converters and oxygen sensors. Do not use this product if foil seal has been removed. www.raceproproducts.com. Made in USA.