Clarence Lai, AKA Airsoft Surgeon, is known for handcrafting fully fine tuned GBB Race Pistols and its accessories. This time around, Airsoft Surgeon designed a 9INE styled threaded outer barrel, that was made specifically for Tokyo Marui based G17 GBB pistols. At the end of the barrel is a 14 CCW thread which will allow you to put aftermarket parts on, such as mock suppressors or compensators.