DUOYI DY223 Electrical Vehicle Voltage Testing And Fault Diagnostic Instrument(Test Clip+Guage Pen+Clip Base)1. Resistance, voltage sorting comparison function, can be customized to set the primary and secondary resistance thresholds and primary voltage thresholds 2. Measure and display the internal resistance and voltage of the test battery at the same time; backlight display is convenient for working in dimly lit places and at night 3. Auto power off to save power If there is no key operation in the measurement or comparison mode, the instrument will be