Battery indicator - SODIAL(R)Digital LED battery status charge indicator Battery indicator 12V / 24V / 36V / 48V / 72V (Black) Works both for 12V / 24V, 36V, 48V / 72V battery. High reliability, low cost and compact size. LED flash for low charge and high charge warning. Specifically designed to monitor the power level of the battery during charging or discharging. Memory option to use amount of current again.