Colt M4/AR15 Receiver Extension Castle Nut P/N: 9390020 Supersedes: 64069, 62357
Factory Colt castle nut for the carbine receiver extension (buffer tube). Locks the extension and end plate to the...
Factory Colt upper receiver assembly to build your AR15, M16 or M4. Compatible with all mil-spec AR15/M4/M16 lower receivers. Includes forward assist assembly, and ejection port cover. Manufactured...