Bingo-shop 2 Cell 7.4V 3 Cell 11.1V Lipo Battery Low Voltage Tester Alarm Indicator Low Voltage Buzzer for2S/3S/4S Lipo Battery New The Alarm sounds and red lights to warn you when the battery voltage is too low. Each LiPo cell = 3.6V (nominal) no matter how many cells are in parallell. Each LiPo has a Minimun discharged voltage of 3.3V before damage occurs