Features: 1.Charging Function: This kind of backpack is designed with USB port that is convenient for you to charge phones when walking making your outdoor life more convenient. 2.Energy-saving: This outdoor shoulder bag is powered by solar energy you do not need to connect any power bank or power source when charging not easy to make trouble for you. 3.Large Capacity: The rucksack is 36-55L that is enough to meet your daily needs you can carry many items when travelling freeing your hands easily and it is suitable for school and outdoor use. 4.Waterproof: The rucksack is made of polyester which is water-resistant and durable you can use it without worries because it protects your items from dust and water. 5.Occasions: Suitable for camping hiking trekking backpacking fishing school travel and other outdoor activities and places this backpack is a good supply for business men and students. Specification: Material: Polyester Color: Light gray black dark blue Size: Approx. 44*29*19CM/17.32x11.42x7.48inch Capacity: 36-55L Solar Panel: USB 2.0 constant 5V output Max Power: 5.3W Best Work Voltage: 5.5V Best Work Current: 0.96A Note: Due to the light and screen difference the item\\'s color may be slightly different from the pictures. Please allow a slight deviation for the measurement data and make sure you do not mind before ordering. includes: 1 * Backpack