Are CO2 blowbacks different from gas blowbacks? Watch this episode of Cybergun's Airsoft User Guide series... "Welcome to our dedicated video about how to properly use our GBB CO2 replicas! In this video you will discover step by step how to setup your replica to prepare it for your next airsoft game, from the HOP-UP setting to the CO2 loading, for a major part of our CO2 replicas."