The classic M4A1 CQB in a gas blowback version. The rifle functions just like the real-steel version. The blowback will give the shooter a recoil and the rifle has both semi and full auto firing mode. Adding to the realism is the Low_Cap magazine which holds 30 rds. A picatinny style top rail on the upper receiver allows for mounting of optical aiming devices. The M4 CQB is full metal and the rock solid gun weighs 3 kilos.