The Lucas Oil 10576 Set of 5 Safeguard Ethanol Fuel Conditioner with Stabilizers is a pack of 5 16 oz bottles designed to clean injectors, valve seats, and combustion chambers while stabilizing fuel. It prevents varnish and gum formation in gasoline and ethanol, protects the engine from alcohol combustion, and combats deposits. Manufactured by Lucas Oil in the United States, this additive is a performance/custom fitment type that offers an unspecified length warranty. Perfect for use in rear placement on vehicles, this product ensures optimal fuel efficiency and engine performance.