Now in stock at eHobby Asia is the second MWS GBB rifle from Tokyo Marui, the Tokyo Marui M4 CQBR Block1... "Every parts of this Rifle are designed to resist to the blowback recoil. The Z-System enhanced the durability of the bolt catch, the piston absorber and the friction relief bolt roller minimize the impact of the bolt's cycle on internal parts, the barrel clamp gives more stability to the barrel and help to keep the barrel screw tightened.