Never worry about your mobile devices running out of power! Designed with industrial-grade solar cells which charge quickly in direct sunlight. Simply plug your original USB charging cable into the USB port provided on the bag and stand in direct sunlight to begin charging! It charges most brands of cell phones & tablets via USB . The backpack is packed with features including multiple zip compartments with pockets for storage and a sleeve for a tablet. The spacious main compartment has a padded sleeve for a 15.4 inch laptop. Sides of the backpack have a zip pocket for accessories and a mesh pocket for water bottle. On the backpack strap there is an elastic mesh pocket for easy access to your phone while charging. The back has extra wide padded backpack straps and a chest buckle for maximum comfort. Finished with a trolley strap for easy transport. Made 1680D Ballistic