Delivered in simple packaging. 【30L Large Capacity｜Expandable】Size: (45+13)cm*33cm*18cm Weight: Approx. 1KG Capacity: Approx. 30L Popular BOX structure/square type + wide gusset, excellent storage capacity, a backpack that is perfect for any scene. It can hold a 17-inch PC, A4 size documents, and enough items for 2-3 days of clothes, and is a large-capacity backpack with smart sorting pockets. There may be small errors due to manual measurement. 【Functionality｜Two-layer｜SBS Zipper】AISFA's unique compact design is the ultimate hidden wet & dry bottom compartment. It is a two-layer type with storage space divided into upper and lower sections. The lower pocket has a waterproof sheet specification, so you can store shoes, lunch boxes, wet umbrellas, clothes, etc. separately in the lower storage space! Especially effective in the rainy season. If the expansion function is not needed, you can close the zipper and put it in the hidden pocket. The zipper uses a high-durability SBS double zipper. You can rest assured that it will not be damaged even if you put a lot of luggage in it. 【Direct Connection Zipper｜PC Storage Space】★Back Zipper: Comes with a convenient back direct connection zipper that allows direct access to the main room. It is very convenient to quickly take out documents and small items. ★Independent PC storage space: The thick cushioning material can protect the contents of the PC and tablet from impact and vibration. 【BOX Three-dimensional Structure｜Carry-on Function】The backpack is a popular BOX structure, square backpack that combines beauty and functionality. It is also used by skiers, campers, and outdoor enthusiasts. The business backpack is equipped with a carry-on function, and the dedicated luggage belt on the back can fix the business backpack to the suitcase for easy movement, eliminating the worry of slipping off. In addition, there is a card pocket on the shoulder, so you can pass through the ticket gate without stopping. 【Water-repellent Finish｜1600D Nylon】The backpack uses PU coating and high-quality 1600D nylon material, which has abrasion resistance, durability, and strength. 【USB Charging Port｜Earphone Hole】There is a USB charging port on the side of the backpack, and you can connect the mobile power supply inside the backpack.