I ordered a complete LMT upper from a board vendor. This is the B/BC that was in the upper. THe upper still had the inspection tag and looked to be in the original box. The upper looks unfired. The B/BC looks to have a few rounds on it.
On the rear top of the carrier there is stamped the following:
PAT #5 911 173/6 044 748 in small print
On the rear ejection port side:
Bolt has a mark 3D and has a o-ring installed under the extractor.
It is unshrouded.
UPDATE: verified with supplier that it is not a LMT and they are going to swap it out.