personal item bag, can fit under the seat of an airplane! 【3-in-1 Travel Backpack with Detachable Laptop Bag】If you're in favor of one-bag business trip, this carry on backpack has got you covered. Featuring a removable laptop bag that fits up to 17" laptop, and well combined the size of a suitcase with the convenience of a backpack, it's easy for business professionals to switch between laptop backpack and travel backpack. 【Zip Expansion to 40L Yet Still Carry-on Compliant】 Overpacker or not? This large travel backpack can be expanded from 28L to 40L via side expansion zippers, offering spacious space to hold 3-7 days' worth of clothes, toiletries, shoes and tech essentials. Even when packed to the max, it meets most popular airline carry-on requirements. 【Thoughtful Organization to Save Your Energy】1- Roomy main compartment with full-open design for easy packing; 2- Dry & Wet separation for wet laundry; 3- Dedicated laptop compartment for computer and tablets; 4- Front vertical zip pocket for your need-it-quick essentials; 5- Back RFID pocket protects your cards and ID documents. 【USB-A & USB-C Port for Effortless Charging】This carry on travel backpack is equipped with a USB power connectivity (integrated USB socket with charger cable), making it easy to keep you charged and stress-free on the move. 2-port design allows for 2 devices charging at the same time or you can even share with your friends. ( Power bank not included )