This is a kind of high quality Soda Stream adapter, made of brass material, with nice durability. This easy to use Soda Stream cylinder filling adapter allows you to fill your own CO2 from your larger bulk cylinder to smaller Soda Stream cylinders. Easy to install and easy to use. You can try it. Features: This easy to use Soda Stream cylinder filling adapter allows you to fill your own CO2 from your larger bulk cylinder to smaller Soda Stream cylinders. Made of high quality brass material, with nice durability. For Soda Stream cylinder filling adapter vent valve W21.8-14 or CGA320 connector. Can be used with large carbon dioxide tanks with CGA320 connectors. Easy to install and easy to use. How to use: Screw the adapter onto a commercially available CO2 cylinder. Empty CO2 cylinder is screwed into the adapter. Open the valve on the large bottle. After about 15 or 20 seconds, the cylinder is fully filled. Close the valve on the large bottle. Open the vent valve. Unscrew the CO2 cylinder. Specifications: Name: Adapter Material: Brass Thread for small bottle: 21*4 Thread for large bottle: W21.8-14 Thread type: Outlet valve diameter 22mm Item size: 45 * 40 * 30mm / 1.77 * 1.57 * 1.18in Item weight: 148g / 5.21ounce Package size: 100 * 60 * 30mm / 3.94 * 2.36 * 1.18in Package weight: 150g / 5.29ounce Package list: 1 * Adapter