Iunio Smart Power Bank 4x 18650 Rechargeable Battery Pack Portable Charger with LCD Display Black It's not only a battery charger box, also can be a power bank for smartphone pc laptop ipad. Powered by 4 pieces rechargeable 18650 batteries, that you can change battery or charge from PC, laptop,wall charger and car charger when they run out of energy. Double USB output. Rapid charge, low power consumption, power lasting. LCD indicates the actual power and interface status. Please use chargers which are below 5V/1A to charge the power bank. Because larger current deducts the battery and component life.