How to Use: 1. Gather the necessary items: a wrench, a gas charging adapter, a large CO2 tank, and an empty quick-connect soda bottle. 2. First, loosen the vent screw, then use a wrench to install our gas charging adapter onto your (CGA320) large CO2 tank. 3. Twist and place the empty bottle into the filling area. 4. Tighten the gas vent valve to securely lock the cylinder. This is the most important step, and a feature of our gas charging adapter, allowing us to fill the soda bottle more safely than with other CO2 gas charging adapters. 5. Slowly open the large CO2 tank and add the CO2 gas to the soda bottle. After about 15-20 seconds, the cylinder be completely filled. 6. Once fully filled, close the large CO2 tank valve first, then unscrew the gas vent valve to release the gas. Remove the soda bottle - done. Color: As shown Material: Metal Package Contents: 1*Soda Co2 Refill Adapter Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.