Colt CR6960 16″ upper. This is the only Colt upper which uses a mid-length gas system. Comes with factory installed Centurion Arms MLOK handguard. C marked carrier and MPC marked bolt. Colt’s CAGE code 13629 will be marked above the forward assist. Fully chrome lined 1/7 twist barrel. These come in the sealed blue Colt bag, but do not come in the blue/white Colt retail cardboard box.