Nuprol Bocca Series 2-7inch FDE Rail Call of Duty The gearbox is a standard

The gearbox is a standard version 2 with Specna's Entre and Convert System which allows the quick change of the spring once the gearbox is removed from the lower

full metal and the quality from KWC we have come to expect

Longer trigger life

which allows you to reduce ROF

Safety lock is placed on the left rear on the frame

Nuprol Bocca Series 2-7inch FDE Rail Call of Duty The gearbox is a standardNurpol Bocca Rail System Series 2 It's not a catchy name, but this rail system is a Airsoft version of the DD Mk18 rail. Description from DD official website: The DD MK18 RIS II is designed to work specifically on the MK18 CQBR The Daniel Defense Rail Interface System (RIS II) was designed at the request of the United States Special Operations Command (SOCOM) for the SOPMOD II program. SOCOM had a specific requirement for a free float M203 solution