Shipped with missing o-ring on extractor - Badger Ordnance M16A2/M4 Bolt Carrier Group (BCG)

So I ran this through it’s paces with my AR build, and noticed it was repeatedly failing to eject the casings and would not cycle. Upon disassembly, I noticed there was no rubber o-ring in the extractor ( most boots come with this). Once I added the o-ring, it worked like a charm. 4 stars only because this is poor quality control. The BCG is sturdy, and once I got it set up properly, it worked the way it should.