Diesel Exhaust Fluid

Diesel Exhaust Fluid (DEF), sometimes referred to simply by the name of its active component, UREA, is a key component of the Selective Catalytic Reduction (SCR) system, which helps diesel vehicles meet strict emissions standards. DEF is a liquid reductant that reacts with engine exhaust in the presence of a catalyst to convert smog-forming nitrogen oxides (NOx) into harmless nitrogen and water vapor.