Colt's Manufacturing CR6920, Semi-automatic, 223 Rem/556NATO, 16.1 Barrel, Matte Finish, Black, Magpul Backup Flip Sight, 30 Round, 1 Magazine CR6920 Throughout the world today, Colt's reliability, performance, and accuracy provide our Armed Forces the confidence required to accomplish any mission. Colt's CR6920 shares many features of its combat-proven brother, the Colt M4.