Originally made by Colt c.1974 as an AR-15 A2 semi-automatic rifle, this item has been reworked by Charles Erb of Fredericktown, PA as a "M16A2" marked full automatic rifle (though the overall features are not all the A2 pattern). Post front and two-leaf peep rear sighs, with an A2 flash hider on "C MP 5.56 NATO 1/7" marked HBAR profile barrel with a bayonet lug, round handguard, low profile casing deflector and forward assist. The lower receiver has both the original commercial and the Erb rework markings, with a right handed three position "SAFE"/"FIRE"/"AUTO" selector, checkered pistol grip and a fixed buttstock. During the upgrade, the trigger pocket was milled out and a pin hole drilled to accept the auto-sear, a full auto trigger group installed, a full auto bolt group ("C" marked carrier, "MPC" head, both matte black), and minor milling to the underside of the upper receiver.