With the SodaStream DUO Black, you can prepare a supply of sparkling water thanks to the 2 included bottles. You get a 1L glass carafe. This allows you to serve cooled sparkling water at home for example. In the other reusable bottle, you can take your sparkling water on the go. Because the bottle is reusable, you use less plastic. You can easily click the bottle into the machine and prepare some sparkling water in a matter of seconds. The more often you press the button, the more bubbles you add. That way, you can adjust the added amount of carbon dioxide to your liking. The included CO2 cylinder is enough for about 60L of sparkling water. And thanks to the Quick Connect technology, you can easily click the cylinder into the machine. You can clean the bottles in the dishwasher after use.