Draper Battery Hydrometer

The Draper Battery Hydrometer is a precision tool designed for testing the solution content in each battery cell. It features graduations of 0.005 g/ml, with color-coded indicators for easy interpretation. The red range indicates a discharged battery, white indicates a battery that requires attention, and green indicates a fully charged battery. Calibrating should be done at 20°C, and caution must be exercised when removing battery cell caps and testing.