This is a 40L backpack by Millet. It's a backpack designed to be carry-on size. I think it can be used in various situations, such as for outdoor activities like mountain climbing, as well as for travel or business trips. I bought it for travel, but I decided to sell it because a suitcase seemed more convenient than a backpack. I've only tried it on a few times since I bought it, and haven't actually used it. This product has a removable waist belt. Please feel free to ask any questions in the comments.