JohnDow JDI-DEF40 Low-Profile DEF CarryTankJohnDow JDI DEF40 Low Profile DEF CarryTank Diesel Exhaust Fluid (DEF) Only 40 Gallon Capacity The JohnDow JDI DEF40 Low Profile DEF CarryTank allows you to easily transport and transfer Diesel Exhaust Fluid (DEF) in the back of a pickup truck. This Low Profile DEF Carrytank is specifically designed to fit within the bed of a pickup truck and below the height of the truck bed sides so you get the convenience of a portable refueling station for your