Product description Material: The backpack is made of durable and practical high-quality canvas fabric, which is very comfortable to handle and not easy to damage. Ergonomic Design: Ergonomic back design for maximum back support and thicker for greater comfort. Breathable, adjustable shoulder straps relieve shoulder pressure. USB Backpack: Provide you with USB function, you can charge your mobile phone at any time when you go out to ensure that your mobile phone is in a smooth state, and the humanized design is more intimate. GREAT GIFT: The special design makes it a great gift for friends on birthdays and holidays, they will be very happy!Product advantages S-shaped shoulder straps, lightweight ridge guard. Shoulder straps and back breathable foam design. Ergonomic. Adjusted and revised by the designer National Ceramics, the shoulder strap design is comfortable and easy to carry. Strap structure: shoulder strap S-shaped design, light ridge protection. High-density foam, stable to carry weight.Product storage Scientific stratification, reasonable storage. Large capacity to meet travel needs.Product SizeProduct details ①Password lock design. The bag is designed with a combination lock, which is safe and anti-theft. ②The shoulder strap is adjustable. The bag's shoulder straps are adjustable for easy access. ③Comfortable portable design The bag is comfortable to carry, and it is not easy to be tired after long-term use. ④Breathable shoulder strap design The shoulder strap of the bag is breathable, and it is not stuffy to carry for a long time. ⑤Smooth zipper design. The bag has a smooth zipper and a smooth zipper. ⑥Triangular reinforcement design. The bag is reinforced with triangles, and the shoulder straps are strong and not easy to damage.