Racor Turbine Series Replacement Diesel Fuel Filter Elements are waterproof, rustproof, and dirt proof. These fuel filters are engineered to repel water and remove solid contaminants before they can damage precision engine components. Racor Aquabloc elements are available in different lengths for various flow rates and color coded for 2, 10, and 30 micron filters. The lower the micron rating, the finer the filtration. Lower micron ratings should be considered when there is no additional downstream filtration.