ALL-NEW RUBBER BUMPER included - protects the 01A from damage. The GPI 01A digital fuel meter series is designed for measuring flow rates from 3 to 30 GPM (10 to 100 L/min) and is factory calibrated in gallons or liters for use with diesel, gasoline, ethanol blends, or kerosene. This digital fuel meter mounts easily to the end of a hose and is ideal for use with free-flow gravity systems or combined with an electric transfer pump as part of a fuel transfer system. DO NOT USE with water or chemicals.