1. External USB charging design, connect to mobile phone power bank anytime and anywhere for long-term battery life, free your hands 2. The back of the backpack adopts high elastic 3D honeycomb back pad, which is soft and comfortable and has good breathability, so that the back can be relieved and kept fresh at all times 3. The back trolley strap design, when you don’t want to carry a backpack, you can travel with a trolley case to free your shoulders and travel long distances easily. 4. The front of the backpack is equipped with a high-brightness reflective strip, which can warn passing vehicles in dim light, making your night travel safer. 5. It adopts waterproof encrypted PVC fabric, which is waterproof and stain-resistant and easy to clean. 6. Capacity: 17 inches/19 inches/20 inches optional
