[Material Description] Polyester [Accessory structure] 3 in 1 backpack set, 17 inch backpack + lunch bag + pencil case [Product performance] Preferred Material: Our product set is made of polyester material, wear resistance, shrinkage resistance and tensile strength. Sturdy: This backpack has reinforced anti-wrinkle details on the bottom to ensure the bottom of the backpack is firm, reinforced to protect the backpack, and adjustable shoulder strap reinforcement. Keep your back comfortable. Lightweight and Portable: Small in appearance but large in capacity, this lunch bag is perfect for your lunch box, snacks, fruit and even protein shake bottles. Meet your daily needs. Easy to carry, pick up and go. Versatility: This pencil case can hold pens, erasers, watercolor pens and other items. Strong functionality, wide range of uses. It is suitable for children's daily school and leisure travel, or office workers who have already worked, and it is a very good combination. [Washing Instructions] It is recommended to wipe and clean with a wet cloth regularly. [Special Note] These size data are measured under the flat, due to different measurement methods, the error within 1cm is a normal phenomenon.