Penray 105032 Total Diesel Fuel System Cleaner - 32-Ounce Bottle Cleans and Helps Prevent Fuel Filter and Injector Plugging Formulated to Dissolve and Disperse Asphaltenes (Black Fuel) Helps Improve Lubricity and Prevent Corrosion Attacks Extreme Cases of Dirt, Grime and Sludge Biodiesel Compatible and ULSD (Ultra-Low-Sulfur Diesel) Compliant