Feature: 1. Support external buttons, connect the button to the K point and the output negative pole, short press to turn on the power display and turn on the 5V output, two short presses in a row will turn off the power display and turn off the 5V output. 2. When the charging current drops to 100mA after reaching the final float voltage, the charging cycle will be automatically terminated. 3. When the battery voltage drops below 4.1V, the charging cycle restarts. When the battery voltage is lower than 2.8V, the battery will be precharged with a current of 180mA. 4. The output will be turned off when the load current is continuously less than 50mA. Support charging and discharging. 5. The USB-A female socket welding position is provided on the back of the product, and the female socket can be installed manually. Specification: Item Type: Battery Charge Module Input Voltage Range: 5~5.5V Charging Cut-Off Voltage: (4.2V/4.35V) ±0.5% Charging Current: 2.4A ± 5% Boost Output Voltage: 5V~5.15V (wire loss compensation) Boost Output Voltage Ripple: 100mV Boost Output Current: 2A Boost Conversion Efficiency: 92.5% (3.6V input, 5V2A output) Battery End Quiescent Current: <30uA . Package List: 1 x Battery Charge Module1 x USB Port