Battery monitor can monitor your battery's voltage status in use. Usually the voltage of battery will drop when it is using, so the battery monitor will monitor the voltage and report you the result with LED & buzzer.
User can connect the battery monitor to the ESC input cable, or connect to the battery balance connector directly.
If the battery monitor detects that load voltage of battery is under 3.3 x N (N=cell number) and stand for 5 seconds, the RED LED will hold the flash status, and buzzer will hold the beep status until you disconnect the battery monitor's power.
1 x battery monitor
1 x connector for 3S battery pack