Features: Low pressure alarm is a Alarm which can indicate 2-3s Lipoions cell voltage situation by the LED and alarm This device can indicate the cell voltage automatically This device can always connect to the battery and monitor the voltage all the time in order to prevent the battery overdischarging Specification: Dimension: 32*18*9mm(L*W*H) Net weight:5g Instruction : Make sure to connect the Lipoion connector to the connector of this Alarm at the same timethe connectors negative of battery must connect to the connectors negative of the alarm When a battery cell voltage is higher than 4.3v the homologous LED will be flashing red light slowly and beep; When a battery cell voltage is between 4.3v to 3.0 the homologous LED will be green persistently; but no Beep. When a battery cell voltage is lower than 3.0v the homologous LED will be flashing red light quickly and Beep Packing content: 1 x Battery Low pressure alarm