Made with Xara To meet the EPA 2010 Nox emission mandate, most large diesel engine vehicles will use Diesel Exhaust Fluid (DEF). DEF is injected into the exhaust stream to reduce the Nox emissions in the engine’s exhaust. We offer DEF solutions from KleerBlue, Graco, and Tuthill: Pedestal dispensers Fleet dispensers Retail mini-bulk tanks Complete packages for retail and fleet Drum and tote packages Petroleum Equipment Diesel Exhaust Fluid