Charging adapter for CO2 refill stations on small welding tanks Please check the thread of your tank before ordering. Outer diameter: 22 mm W21 8-14 / DIN477 / M22-14 of your large CO₂ tank. Common in: Russia, Korea, Japan, Great Britain, France, Switzerland, Sweden, Ukraine, Germany, South Africa, Czech Republic, Singapore, etc. With this item, you can fill your small CO₂ tanks with CO₂ from your large tank, making it easy to refill your small tanks. CO₂ refill station, charging adapter type: W21.8-14. How it works: For correct use, please follow our instructions: 1. Chill the bottle in the freezer for 1 hour. 2. Screw the CGA320/W21.8 connector onto a standard CO₂ gas cylinder. 3. Disconnect the quick-connect fitting from the black adapter and then tighten it onto the cylinder (turn the knob on top of the adapter to the uppermost position; the knob does not need to be turned down to open the cylinder. When the adjusting rod presses against the 6 mm wide valve pin, the valve closes and CO₂ cannot flow in). 4. Reconnect the quick-connect fitting. 5. For most large cylinders: Turn the cylinder upside down or lay it on its side. (Some tanks do not have a dip tube.) 6. Carefully open the valve on the large gas cylinder (the valve on the cylinder will shut off the flow if it is opened too far. This happens if the cylinder is opened too far/too quickly, so open the cylinder very carefully. You will hear the airflow to ensure successful filling). 7. After about 15–20 seconds, the cylinder will be completely full. 8. Close the valve on the large gas cylinder. 9. Open the vent screw to release any residual gas. 10. Unscrew the CO₂ cylinder. Color: Black Material: Metal Package Contents: 1 * Charging Valve Connector Only the above package contents are included; other products are not included. Note: Light reflections and different screen settings may cause the color of the item in the picture to be slightly different from the actual color. The allowable measurement deviation is +/- 1-3 cm.