The Delphi Difference: hen compared to other filter manufacturers is that their products are designed to keep up with high pressures and fine tolerances - ensuring the longest possible product life. Removing particles down to as little as 2 microns in size delivering optimum protection of the fuel injection system. The Patented technology and high efficiency, multi layered designs are available for a wide range of vehicles. The Delphi-Cav fuel filter water separators are suitable for fuel filtration and water separation. Replacement DPFs also available.