This is a replacement glass tube for the Kanger Mini Protank 2, Mini Protank 3 and Mini Aerotank. It comes in a selection of colors: red, purple, blue, clear and smoke. It is easy to replace the tanks on these three devices and so if your break them, then you do not have to replace the whole device. You may also decide that you would like to change the color and customize your device and as they are not that expensive it can be a great and fun thing to do. If you prefer a colored tube then you can buy this and keep your original as a spare or you might want to buy one of these as a spare. Although the pyrex glass is fairly string, if you are clumsy or think it is likely to get damaged by being dropped or crushed, then it is wise to have an extra one.