Opti-Lube XPD Diesel Fuel Improver: 1 Gallon without Accessories Treats up to 512 Gallons Enhanced Lubricity for Reduced Fuel System Wear Improved Fuel Economy, Increased Power Cleans Injectors and keeps them clean! Reduced Deposits and Emissions. Prevents Rust & Corrosion Improved Water Separation, Cold Weather Performance and Storage Stability (More than doubles storage life of diesel fuel) Compatible with all vehicle emissions systems