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USB 3.7V battery charger 2.5mm jack
maximum current is 300mA, and cable length is 55CM. Balanced charging 4.2V

The USB terminal has a charging indicator light. When charging the indicator light does not light. When the battery is fully charged, the indicator light is on.

Instruction:
1.When connect to computer without battery and the LED is on,that means it will be off when charging.
2.When connect to computer without battery and the LED is off,that means it will be on when charging.
3.Do not use or charge the battery when it is hot.