What are your gas cylinders made from? Grace 09 January 2023 02:53 The body of our CO2 cylinders are aluminum while the valves are brass. Enjoy the durability of our cylinders! Related articles How often will I need to replace my gas cylinder? Why is SodaStream phasing out their 30L gas cylinders? Which carbonating bottles fit my Sparkling Water Maker? Will high altitude have any effect on my cylinder and can I take my cylinder on a plane? What's the difference between exchange versus spare gas cylinders?