The M4A1 AR15 style Upper Receiver Group is built around a 14.5 inch Cold Hammer Forged M4 Profile barrel with a permanently attached Daniel Defense Flash Suppressor, a GRIP-N-RIP Charging Handle, and our mid-length gas system. It features a 12.5 inch lightweight RIS III rail—modeled after the revolutionary RIS II two-piece handguard developed for SOCOM—features M-LOK attachment for lighter weight while still offering M203 grenade-launcher attachment. All Daniel Defense complete upper receiver groups come standard with an M16 profile bolt carrier group. SERIOUS buyers ONLY!!! Please ! NO TRADE!! Contact me for any concern 9oFour-3twoTwo-four2o2 BOX is not INCLUDED!!