Opti-Lube XPD Formula Diesel Fuel Additive: 4oz 8 pack Treats up to 16 Gallons per 4oz bottle Enhanced Lubricity for Reduced Fuel System Wear mproved 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