for CO2 Cylinder Tank Refill Adapter Fill Station. Thread for TR21x4, Allows to use most for Machines. With Quick Disconnect Connector. This Item Use for / Soda Club To External Tank Cyclinder Connect.Like 5lb, 20LB or 50lb commercial CO2 tanks. This item can't fit Australia or New Zealand for bottles. Our Adapter 't Work Residual Pressure Valve (RPV valve). Please 't disconnect the quick disconnect under pressure, it will be blowed out the o ring in quick disconnect(female QD),Use bleed valve drain residual pressure. How it works: Screw the adapter to a larger CO2 gas cylinder. The empty for cylinder is screwed into the fill adapter. Connect quick disconnect. Open the valve of the gas bottle. Wait for the cylinder is completely fill, about 30 sec. Close valve of the gas bottle. Opening the Vent bleed valve screw to drain residue remaining gas. Unscrew the CO2 - done. Thread To Big Bottle: CGA320 CGA320 connector CO2 Tank Common in USA, CAN, Brazil, Colombia, Philippines. Model Number: Universal Weight: 289G Type: Air Systems colour:Blackandsilverandgold Material:Copper and stainless steel size:Length: 143mm Package Contents: 1 x adapter 4 x spacers Only the above package content, other products are not included. Note: Light 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.