[ Premium Aluminum Alloy]: This CO2 adapter is made of premium aluminum alloy, which has excellent resistance, fire resistance, and moisture resistance. Its sturdy structure provides excellent sealing, , and anti-rust performance, ensuring long-term durability and reliability. DUO, for ART, for TERRA, for E-DUO, for Crystal 3.0, and for . It fits standard 60L CO2 cylinders equipped with traditional TR21-4 trapezoidal threads, facilitating the connection between old CO2 cylinders and new soda machines. [Universal Compatibility]: This CO2 quick adapter is designed to be seamlessly compatible with a variety of soda machines, including for [Convenient Split Design]: This adapter features a split design, allowing for easy installation without removing the base of the machine. It is suitable for new models with for QC Connect such as for Terra, for DUO, and for ART, ensuring a secure fit without causing any damage to the device. A spare rubber ring is included for maintenance. [Cost-effective Solution]: By using this CO2 adapter, you can continue to use your CO2 cylinders for both new and old soda machines. Not only does this the hassle and expense of purchasing new cylinders, it also extends the usability of your existing equipment.