This is a LARGE pivot pin flat top Colt Competition upper. It has the following:
20 inch H-Bar marked CMP 556 NATO 1/9
There are a couple of minor scratches on barrel
Original Colt Bolt/Bolt carrier and charging handle
A2 flash suppressor and NO bayo lug.
The receiver is in excellent condition with no blemishes.
I'm not sure how many rounds have been through it, not many. Definitely less than 1000 and almost certainly less than 500. This is an original Colt built upper, not a parts upper. $675 shipped. I can e-mail pics.