This used Centurion Tactical CT-15 rifle fires the 5.56mm/.223 round. It has a 16" barrel with an overall black finish. This semi-auto rifle has a permanently affixed flashhider, a collapsible stock, a quad railed forearm, and a rubber pistol grip with storage. This rifle comes with rail covers, an A.R.M.S. flip up rear sight, and one 30 round magazine.