The professional mountaineering bag looks very big, but actually it can't hold much, because the back part is covered with a layer of plastic, which makes the back part empty to ensure the heat dissipation on the back. Therefore, it is not recommended to endorse in school, because the book will be damaged and the notebook will not fit. If you go to school at ordinary times, it will be very different. It is more handsome to buy some fashionable bags.