How to charge Amazfit Band 2?
When you double tap the button and the screen is not lit or the battery is low, please charge the band immediately. Following the instructions, please stick the USB charging cable to the charging contact on the back of the band, and connect the USB interface on the other end to a mobile phone charger or computer USB port with a rated output voltage of 5V and an output current of 300mA or above to charge the band.
Notes: The voltage of all computer USB interfaces is 5.0V. Fast chargers with the charging voltage of 5V can also be used for charging the band.