The Respironics EverGo Accessory Bag is quite deceiving. From the outside you see that it has one big pocket, but it doesn't seem like it will hold that many accessories. However, the interior of this accessory bag is very roomy and easy to organize. With an elastic strap in the main pocket, your accessories will stay in place while you go about your day. There are an additional 3 pockets inside the bag, with more than enough room for extra batteries, your power supplies, and more. A lot of portable oxygen concentrators come with accessory bags that you are required to carry with you if you wish to bring it with you. However, the EverGo accessory bag simply slides over your travel cart, allowing you to keep one of your hands free. This convenient storage solution keeps all your essential accessories organized and easily accessible while minimizing the load you need to carry.