Colt LE6921 Upper Receiver Assembly 5.56 NATO 14.5" Chrome Lined Barrel, Black - LE6921CK

Complete upper receiver assembly for AR-15 rifles, chambered in 5.56 NATO/223 Remington with a 14.5" chrome lined barrel (1:7 RH twist). Includes bolt carrier assembly, charging handle, M4 contour barrel, flip-up rear sight, bayonet lug, and screw-on flash hider. Mounts to Colt lower receivers via included pivot pin adapter; note that the included bolt carrier assembly may not be compatible with some Colt rifles equipped with steel sear blocks.