TELESIN Dual Charger + 2pcs 3.7V 1010mAh Li-ion Batteries Battery Pack for Xiaomi Yi Xiaoyi Action Sports Camera TELESIN Dual Charger: Charging AZ13-1 battery, can charge 2 batteries at the same time. Design input: DC 5V, actual charging time based on input electric current. Can be powered with most standard USB chargers, eg: wall charger, car charger, PC USB port, power bank. The indicator light signal: GREEN means empty or full; RED means charging in process. TELESIN Li-ion Battery Pack: 3.7V, 1010mAh, 3.7Wh Li-ion batteries.