Nine Ball 6.00mm TM GBB Pistol Inner Barrel (Hicapa / Glock 17)Nine Ball 6. 00mm TM GBB Inner Barrel Nine Ball has been providing tested and well designed aftermarket parts for airsoft for quite some time. This makes them a go to brand for performance upgrades. The Nine Ball 6. 00mm Tightbore barrel gives your airsoft pistol a boost of accuracy with its metal construction and refined finish. Compatibility list: Glock 17 Length: TM WE KJW VFC Glock 17 and 18, Sig P226 series Hicapa 5. 1 length: TM WE KJW Hi capa