Petra's ethanol fuel treatment & stabilizer, No. 2005, can increase gas mileage and prolong engine life. Fuel additive can counter the harmful effects of ethanol fuels. Each bottle can treat up to 21 gallons of fuel, improving combustion and engine performance. A list of features and benefits include: keeping fuel fresh longer, cleaning injectors and fuel system components, preventing phase separation and corrosion, and works in both recreation and utility environments.