OPS-STORE puts out the a video to help you maintain your own gas blowback rifle or if you want to become an airsoft tech... "OPS-Store presents you with a complete maintenance guide for your GBBR replica. Do you want to maximize the performance of your replica? You are in the right place ! In this video, we present a complete maintenance guide for your GBBR (Gas Blowback Rifle) replica. Whether you are a novice or a veteran, we have put together in one video tips and advice to ensure the proper functioning and longevity of your GBBR replica."