It is a very convenient laptop bag, could be a backpack, shoulder bag, even a portable bag. Canvas or nylon material, it is depend on customers' option. water resistasnt, no afraid of small raining day.  Use top quality material, with PU comfortable handle, durable and detachable shoulder strap, two way zipper. Padded shoulder strap, breathable and comfortable, the shoulder strap could be hidden on back, and use the bag as a portable bag. Very large capacity, fit up to 17.3inch laptop. The bag with a luggage belt, could be put on a trolley case.