Colt M4 Barrel marked "C MP 5.56 NATO 1/7", in overall great condition. I can't remember the exact number through it though my guess is that it is around 500 rounds. This barrel has a standard barrel extension and non F-marked FSB.
If you would like pictures and are serious let me know and I'll take a few. Otherwise, it looks like every other Colt M4 barrel out there.
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