Rechargeable Battery Blucell (AAA) These type-C rechargeable batteries are pre-charged and ready to use straightly from the box. They will hold a full charge for up to 12 months when not in use. How to charge the batteries Connect Type-C cable to the batteries and suitable USB power source (such as mobile phone adaptor, laptop, powerbank or car charger). Several batteries can be charged at the same time. A red LED will blink when charging and remain on when fully charged. One full charge will take about 1.5 hours , , SAFETY WARNING: How to charge the batteries Connect Type-C cable to the batteries and suitable USB power source (such as mobile phone adaptor, laptop, powerbank or car charger). Several batteries can be charged at the same time. A red LED will blink when charging and remain on when fully charged. One full charge will take about 1.5 hours Keep out of reach of children. Insert correctly, observing the polarity markings (-/+). Do not mix with any other type of battery. Do not disassemble. Do not dispose of in a fire. Do not Leave unattended while charging. Disconnect when fully charged. Failure to follow these safety instructions could result in fire, electric shock injury or damage to persons, product or property and will invalidate the guarantee.