Asura 12 gram CO2 cartridges are designed to be used as power cartridges for your airsoft guns. It works with BB and paintball guns too. The CO2 cartridge provides a consistent power source for your gun so that you can quickly replace the cartridge with a new one and continue playing your airsoft game. <p><b>Warning: The CO2 cartridge becomes very cold during operation. Take precaution when you unload an empty cartridge from your magazine. It is a good practice to wear gloves or equivalent when you handle the cartridge in order to avoid freeze damage.</b></p> <p>Please note that the 12 gram CO2 cartridges are not designed for CO2 drain line cleaner or CO2 bike inflator. These devices normally use 16 gram threaded or unthreaded cartridges. The 12 gram cartridges simply do not work on them.</p>