Complete 16" Anonymous Arms 5.56 Forged Upper Receiver with a mid length gas system and a Nitride 4142 Steel Socom Mid Length barrel with a 1/7 Twist. Fortis REV-12 Free Float Rail and KAK 1/2x28 Flash Can. All Mil-spec, US Made parts including a Nitride Bolt Carrier Group. Solid steel low profile gas block. HPT (High Pressure Tested) and MPI (Magnetic Particle Inspected) Bolt and Barrel. Charging handle included.