The Willison Products FUPRO (Fuel Protection) Diesel Fuel Filtration System is designed to detect and prevent water from entering the fuel injection system while purifying the fuel with a two micron filter. A water separator with a clear bowl shows any water present. An in-cab gauge, which monitors the change in either pressure or vacuum in the fuel system, indicates when it is time to change the fuel filter or drain the water. This system is biodiesel compatible, stops filter clog problems and prevents engine damage from contaminants. Made in the U.S.A.