Caterpillar 1752949 175-2949 FUEL WATER SEPARATOR Advanced High Efficiency Multipack (Pack of 3) Advanced Efficiency Fuel Water Separators are designed to eliminate 100% free water and 90% emulsified water along with smaller contaminates while helping extend the life of your secondary filter and expensive injectors. Cat Fuel Water Separators are built to extend the life of your secondary filter and precision fuel system components. Efficiency Rating: Advanced Efficiency Primary vs Secondary: Primary