The Inogen One G3 system includes a carry bag to carry the concentrator on your shoulder. But if you're looking for more carrying comfort, this backpack is what you want!Because you carry a backpack on both shoulders, the weight is distributed more evenly. And this bag has a strap around your waists, also carrying a part of the weight. This way the Inogen One G3, which is already very light from itself, becomes even lighter!