Item features: Material:Material: Aluminum alloy, Copper Col: gold; lilac silver Topic: TR21-4 Function: Connect the soda cylinder with TR21-4 thread to the DUO, TERRA soda machine with quick connection cylinder Properties: 1Fits many common CO2 cylinders which have the conventional trapezoidal thread TR21-4, bottles with up to 60 litre 425g CO2. Made of sturdy extra light aluminium. environmentally friendly, robust, high safety, stainless durable. 1. Remove the pink piece from the bottom of the Terra Water Sprinkler by pressing the pins as shown in the supplied instructions pulling the device out downwards. F the DUO ART bubblers, a small piece of the housing must be cut out in the cylinder compartment so that the cylinder can be inserted into the compartment. 2. Screw our quick adapter with the inserted flat seal firmly onto the conventional TR21-4 valve. Fits perfectly on our 425g CO2 cylinders but of course also on the cylinders of other manufacturers such as the Crystal 2.0, Penguin, Cool Aqvia. IMPTANT: If the adapter cannot be screwed into the CO2 bottle HLE, this cylinder is not compatible with this adapter. If you have any questions, we are happy to answer them. 3.Insert the 425g cylinder into your Soda DUO, Art Terra fix it as usual by pulling down the quick release device pressing into the water spreader until the device clicks into place. IMPTANT: The hexagonal screw (safety valve) of the TR21-4 valve must be positioned so that it looks OUT of the device NOT sideways into the stage device. Why choose us? What if you only have a blue CO2 bottle but are too lazy to go out refill? are there no gas stations nearby? The improved quick adapter from WADEO, specially developed f sparkling water heaters with pink CO2 bottles. If you only have the blue CO2 bottle, take this adapter home, you can refill the blue bottle directly, then add the adapter, then you can use it on Terra/Duo/Art series Sodastream soda machines. Scope of delivery: 1Quick Adapter