The DAHL system takes care of those shortcomings. DAHL’s functional dual-chamber 3-stage diesel fuel filter/water separators provide efficient suction side water separation and contaminant filtration. The key is the unique DAHL patented depressurizer cone, which spreads the flow of the fuel. With more area to flow over, greater separation of water and dirt from the fuel is achieved. DAHL fuel filter/water separators have less mechanical flow resistance than other separators, because the fuel changes direction only twice. The DAHL unit removes virtually 100% of the water and most of the contaminants from the fuel.