Because the Co2 will expand as it enters a warm cylinde, so you 't get enough CO2 in there, a glove is needed to hold the cold cylinder. It only fit for pink Co2 cylinder system with quick connect valve(no thread). Easy Installation: With the CO2 Refill Adapter,You can fill CO2 cartridges simply yourself by connecting a commercial CO2 bottle with your pink CO2 cylinde with quick connect. Function upgrade: It is no longer necessary to exchange your empty CO2 cylinders,no Complicated towing with our filling adapter,It built from quality materials for durability. Type:W21.8-14 Colour:Gold Material:brass Package Contents: 1 x CO2 Tank Adapter 1 x Install seal fittings Kit 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. Because the Co2 will expand as it enters a warm cylinde, so you 't get enough CO2 in there, a glove is needed to hold the cold cylinder. It only fit for pink Co2 cylinder system with quick connect valve(no thread). Function upgrade: It is no longer necessary to exchange your empty CO2 cylinders,no Complicated towing with our filling adapter,It built from quality materials for durability. Easy Installation: With the CO2 Refill Adapter,You can fill CO2 cartridges simply yourself by connecting a commercial CO2 bottle with your pink CO2 cylinde with quick connect.