1. Cotton ramie surface, water repellent, wear-resistant and scratch-resistant 2. Lightening burden design, fits the back, comfortable and breathable 3. Multi-layer storage pocket, convenient to classify and carry personal belongings 4. Whit external USB port, can charge the phone at any time (power supply not included) 5. Can hold 15.6-inch laptop 6. Size: 30x11x43cm 7. Weight: about 680g