Samfolk Backpack Commuting Business Bag Waterproof 4-Way Multi-functional Pockets 17-inch PC Compatible Durable Shockproof Carry-on Carbon Black 【Amazing Expandability & Smart Large-Capacity Storage】 From a business backpack to a travel bag perfect for short business trips. Expand the capacity from 20L to 30L with just one zipper. You can store A4-size documents, suits, and computer peripherals all together. Furthermore, the self-supporting design makes it incredibly easy to take things in and out. It stays organized without tipping over, even in the office or hotel. 【Size】 (Before expansion): 45 x 34 x 12cm Capacity: Approximately 20L (After expansion): 45 x 34 x 20cm Capacity: Approximately 30L 【High-Quality Nylon Material & Excellent Waterproofing and Stain Resistance】 Made with high-quality, tough material suitable for business settings. The high-density 900D leather-like nylon is coated with water-repellent treatment, so sudden rain, splashes, and minor stains can be easily wiped away. 【Reliable Protection & Versatile Pockets for Easy Organization】 An independent PC pocket with high-density cushioning and a fixing belt to securely protect laptops up to 17 inches. It reliably guards valuables from impact. Furthermore, the front A4-size front pocket and dedicated waterproof pocket, etc., allow for neat organization with multi-functional divider pockets, making it easy to take things out. A theft-prevention pocket on the back securely stores valuables such as mobile phones and passports. 【Comfort & Excellent Breathability】 Adopts S-shaped shoulder straps to reduce the burden on the shoulders and back. By effectively distributing the weight, the design makes it less likely for your shoulders to hurt, even on days with a lot of commuting or travel. In addition, it is equipped with a breathable structure using 3D mesh back panel material on the back. It eliminates stuffiness and discomfort, and provides a comfortable carrying experience even in hot seasons. 【Travel Convenience & Commitment to Durability in Detail】 Equipped with a strap on the back that can be directly attached to the carry bar of a suitcase. This makes moving much easier, freeing up your hands and allowing you to move smartly. High-intensity reflective material is placed on the back shoulder straps. It enhances visibility from the front in the dark and strongly supports traffic safety during nighttime travel. Also, all parts that are subject to daily stress and wear are thoroughly reinforced. A USB charging port is also included, allowing you to charge your smartphone while traveling (battery sold separately).