Specifications:Large storage space, large main bag can hold A4 magazines, daily clothes and other items. Breathable back, comfortable to carry, the back is made of breathable sponge, soft, comfortable and breathable.Material: polyester/canvasOpening method: zipperApplicable gender: neutralFunction: breathable, waterproof, wear-resistantWeight size:3 pieces: 0.55kg;17-inch backpack: 0.30kg; 44 * 28 * 13cmShoulder bag: 0.18kg; 25 * 19 * 8cmPen box: 0.07kg; 22 * 11 * 5cmPackage includes:1*pen bag or1*shoulder bag or1*backpack or3 pieces (pen bag + shoulder bag + backpack)Note: 1. Due to manual measurement, there may be a slight error of 1-3cm.2. Due to the difference between different monitors, the picture may not reflect the actual color of the item.3. If you need to buy 3 pieces (pencil case + shoulder bag + backpack), you must choose the SKU of 3 pieces. If you buy a pencil case, the package you receive will be just a pencil case, not 3 pieces.