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Holy Stone 2pcs Rechargeable Li-po Battery 7.4V 2500mAh and 2 USB Charging Cables for RC Quadcopter Drone HS100 BlackWork for Holy Stone HS100 and HS100G RC Drone Quadcopter
Kit Entails: 2 * 7.4V 2500mAh Li-po Batteries, 2 * USB Charging Cables
Battery Voltage: 7.4V ; Max Charging Time: 3-6 hours; USB Cable Voltage : 5V
Charging State: Before every little thing, the rightmost light on the battery blinks in blue and when the battery is totally charged all four lights flip steady in blue.
Charging Diagram: Connect the charging cable to PC USB port or a phone adapter (5V, 1-2A)