Large capacity backpack: 16.1 X 11.8 X 4.5 inches (41 X 30 X 11.5 centimeters). There may be errors (1-2cm) during the actual measurement process, and the actual size is based on the specific product size. fabric: The backpack is made of polyester fabric, which is tear resistant, scratch resistant, comfortable, breathable, and easy to clean. The storage bag is made of cotton and linen fabric, which is durable and easy to store. Ergonomic design: According to the principles of ergonomic design, it consists of a shoulder strap composed of a three-dimensional mesh and multiple layers of sponge to ensure optimal pressure release and comfortable carrying. Applicable occasions: Suitable for any occasion, such as daily school, outdoor sports, shopping, fitness, gatherings, picnics, or travel. When going out, you can put various items you want to carry in your backpack. After sales service: If you have any questions about this product, please and we will reply to you as soon as possible within 24 hours. Happy shopping! Note: Due to the light and screen setting difference, the item's color may be slightly different from the pictures. Please allow slight dimension difference due to different manual measurement.