Water is your engine's number 1 enemy - no matter how carefully fuel is handled, water and other contaminants can find their way into it. Protect your engine with a Racor fuel/water separator. Diesel engine fuel systems recirculate fuel, actually "creating" water when warm fuel returns to a cold tank. Using a fuel filter/water separator ensures that fuel arrives at your engine clean and water-free. Most stock filters only filter particles from the fuel, allowing water to pass through your fuel system, causing rust and corrosion. Using a patented "Aquabloc" element, Racor fuel filters remove emulsified water and particles down to two microns in size. Fittings not included. For UL and USCG accepted filter/separators, call our Engine Parts Specialists at 800-528-4828.