Saves gas & helps peak performance. 1 bottle = 1 use. Deep-cleans fuel system! Treats up to 21 gallons. America's leading fuel additive maker! Use every oil change or 4,000 miles. STP Complete Fuel System Cleaner has our maximum dosage of deposit-fighting detergents to help: deep-clean the entire fuel system; save gas and lower emissions by removing deposits throughout the fuel system; reduce need for higher octane fuel to stop knock and ping. STP does not manufacture any private label products. Made in the USA.