Top notch Bolt Carrier Group for sure. HP/MP tested and marked bolt, great staking, and just great specs overall. I've heard rumors about who is the manufacturer for these bolts and you'll be hard pressed to find anything this high quality for any cheaper.
Bolt is marked HPT/MPI and carrier is properly staked. Gas key appears to be machined billet, not cast. Great price for a mil-spec/OEM BCG w/ C158 bolt.