Selling a Block 2 M4A1 clone upper receiver - never been fired and treated like a safe queen. Professionally built by D Wilson Mfg. Colt cage code upper, Colt C-stamp BCG, Colt cage code barrel cut down to 14.5 and p/w Surefire 4-prong muzzle device, DD RIS II Rail, and Magpul AFG. Only thing missing is charging handle. Asking 500. Priced for a quick sale, no lowballs or trades.