Opti-Lube Winter Formula Diesel Fuel Additive: 1 Gallon without Accessories Treats up to 512 Gallons Enhanced Lubricity for Reduced Fuel System Wear Improved Fuel Economy, Increased Power (Cetane increase up to 3 points) Cleans Injectors, reduceses Deposits and Emissions. Prevents Rust & Corrosion Improved Water Separation and Storage Stability (More than doubles storage life of diesel fuel) Contains Anti-Gel, fuel will flow down to -40 F**