100% Original and Goo d Quality with Free After-sale Warranty . All types of CO2 cylinders can be used. With this quick adapter, you can continue to use traditional screw valve CO2 cylinders. This adapter can be used with almost all 425 gram aluminium CO2 cylinders with screw valve from different suppliers. With just one hand, your CO2 aerator (type DUO) can be used with this adapter. Thread: TR21-4 Height: 37mm Outer diameter: 36mm color:Silver Material:aluminum Package Contents: 1 x Adapter Only the above package content, other products are not included. Note: Light reflection 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.