GO2 Weapons MK18 is our original Close Quarters Battle Rifle. Chambered in 5.56 NATO along with its proven reliability and compact frame makes it the Ultimate CQB platform. The match grade 11." SEPR barrel enhances the weapons accuracy when the operator is forced to engage targets at longer distances. The barrel's special profile allows for longer full auto run time if required. The MK18 utilizes a combat trigger that provides the shooter with a crisp, clean trigger pull for ultimate control. The GO2 MK18 was designed from the ground up with close quarter battle in mind for todays Modern Day Warrior.