Lucas Safeguard?Ethanol Fuel Conditioner and Stabilizer was developed to specifically address issues associated with using ethanol based fuels. This applies to E-10, E-15, E-85, pure ethanol and any mixtures in between, including gasoline. Our product is completely soluble in all ethanol fuels and will not harm filters. Our product contains effective additives to prevent rust and corrosion associated with the use of ethanol fuels. Safeguard? cleans injectors, valve seats, combustion chambers and other critical fuel components. It contains effective oxidation inhibitors to stabilize fuel and prevent varnish and gum formation in ethanol and gasoline. It works to combat deposits and protects your engine oil lubricants from the harmful effects of alcohol combustion. Safeguard? treats up to 80 gallons (302.8 liters) of ethanol fuel. One ounce treats five gallons of ethanol fuel. Recommended for use in automobiles and marine applications. Our new 5.25 oz bottle treats up to 25 gallons (94.6 liters) of ethanol fuel. NOT RECOMMENDED FOR DIESEL APPLICATIONS.