Features 1、This is a under-voltage switch controller used to turn off the power of load in the event of the voltage dropping below a set value 2、When the battery voltage increases to a set value, the module will automatically turn on load again 3、Designed with a LED indicator to show if battery is under-voltage 4、Both turn-off and turn-on voltage value can be adjusted by simply pressing buttons 5、This controller will help you to protect battery from over-discharging and prolong battery life Specification Features: This is a under-voltage switch controller used to turn off the power of load in the event of the voltage dropping below a set value. When the battery voltage increases to a set value, the module will automatically turn on load again. Designed with a LED indicator to show if battery is under-voltage. Both turn-off and turn-on voltage value can be adjusted by simply pressing buttons. This controller will help you to protect battery from over-discharging and prolong battery life. Specifications: Suitable Battery: Storage/lithium battery Power Supply Voltage: DC12V Battery Voltage: 3.7V~96V Control Voltage: 3V~120V Control Current: 20A Control Precision: 0.1V Voltage Error: ±0.1V Size: 7.8*4.3*2.3cm/3.1*1.7*0.9in Weight: 42g(approx.) Voltage Setting Method: At setting mode(when display flashes), S1 button increases voltage value(add), S2 button reduces voltage value(minus). S1 Under-voltage Setting(load stop): At normal mode, press S1 button to show under-voltage value. Press and hold S1 button till display flashes, then adjust under-voltage value by pressing S1 and S2 button. S2 Over-voltage Setting(load start): At normal mode, press S2 button to show over-voltage value. Press and hold S2 button till display flashes, then adjust over-voltage value by pressing S1 and S2 button. Restore to Factory Setting: At normal state, press and hold S1 and S2 buttons together, till display shows 888, to restore to factory setting Note: If S1 cannot be used to add voltage, set S2 first; if S2 cannot be used to minus voltage, set S1 first. Package Includes: 1 x Battery Under-voltage Controller Package List