Improve your fuel economy and get cleaner emissions from your car when you add the BlueDEF Diesel Exhaust Fluid to your exhaust stream. BlueDEF is a non-toxic, non-flammable fluid that helps remove nitrogen oxide from your emissions. It converts the NOx into harmless nitrogen gas and water vapor. This mixture of urea and deionized water is completely water soluble, stable, colorless, and odorless. It comes in a convenient 2.5-gallon jug so you can store it in your trunk when you're running low. Make the earth and your wallet a little greener with BlueDEF Diesel Exhaust Fluid.