Diesel engine vehicles equipped with Selective Catalytic Reduction (SCR) systems produced after January 1, 2010 are required to use Diesel Exhaust Fluid (DEF). CF Industries’ DEF, TerraCair, is a composition of urea and water, used in such diesel engines to reduce the amount of nitrogen oxides (NOx) emitted into the air. Use of TerraCair not only meets the 2010 tailpipe standard, but also delivers significant fuel economy for your vehicle!  CF Industries is the largest North American producer of DEF—they control and oversee the entire distribution chain, so you can be sure that all products comply with ISO 22241.