... the charge of sunlight, you can also use ordinary, alkaline batteries to let lamp light, so you can always move ... Charger Type : Solar Charge / USB / alkaline batteries·Built-in Rechargeable 3.6V, 600 mAh Ni-Mh battery ·Charger Indicator : Solar charging indicator ... / Charge lasts up to 4 hours ·Battery backup - 3 AAA alkaline batteries / Use AAA alkaline battery for 48 hours of light life ·Portable ...