Sta-Bil Marine Ethanol Fuel Stabilizer & Treatment. 32 oz. Bottle 1 Oz. treats 5 gallons. America’s #1 Selling Marine Fuel Additive Brand. Best Ethanol Problem Fighter. More than FOUR TIMES the Fuel System Cleaner than in Regular STA-BIL DOUBLE the corrosion preventer than in Regular STA-BIL Prevents corrosion from moisture & ethanol-induced water attraction. Improves marine engine performance YEAR-ROUND, not just for seasonal storage.