Suitable Specification: The CO2 cylinder adapter is suitable for TR21-4 male valve, which can ensure quick and stable connection with the soda machine. Premium Material: The CO2 cylinder adapter is made of high-quality aluminum alloy material, which is sturdy, stable, and highly reliable, and can be used for a long time. Easy To Use & Carry: The CO2 cylinder adapter is lightweight, portable, and easy to use, you can convert it by yourself. Wide Application: The CO2 cylinder adapter can be used for regulating valves in aquarium CO2 cylinders and soda machine. Shop With Confidence: To provide you with the highest quality service, if you have any question, please contact us. We will provide reply until you are satisfied., Weight: 0.1763698096 pounds, Manufacturer: BDKMMS