This upper consists of an olympic arms 16" heavy chrome moly barrel in excellent condition with a mirror bore and chamber. I received the barrel in close to new condition and shot about 140 rounds through it. The barrel is mated to a Colt A2 receiver in good to very good condition. (The receiver was demilled by the removal of the forge mark "C" - the "M" remains representing Colt and Martin Marietta) It comes with single shield M4 handguards and charging handle. No bolt or bolt carrier included. It is an excellent shooter. I have sprayed the barrel and receiver with matt black Brownells Alumahyde II to make the barrel and receiver a uniform black color. I have several AR's on which I have used Alumahyde II and it is a good product. I am selling it because I prefer 20" barrels. Put your own bolt in and you'll have a complete upper for under $300.