This simple but important part will stop liquid CO2 from entering your marker. Liquid CO2 is very unstable and makes your marker shoot inconsistent. Another reason to use an anti-siphon is liquid CO2 breaks down o-rings due to the cold temperatures of the gas. The anti-siphon can help you save time and money by protecting those valuable o-rings!
Make sure you have a qualified technician install any anti-siphon to your CO2 tank.