Backpack size: 11.5 "x 5.5" x 16.7. It is made of polyester material. It is light, beautiful and firm. It is waterproof and scratch proof. It has large capacity and sufficient space to store many items.There is a large capacity main bag and a computer compartment inside the backpack.Two zip pockets in the front and one zip pocket in the back. There are two side pockets on both sides, which can hold water bottles or umbrellas.The front pocket of the backpack has a zipper compartment. The backpack can be folded into a small bag, which is convenient to carry.Backpacks can be used in many occasions, such as running, hiking, riding, traveling, mountaineering , bringing you a relaxed and free feeling.