The Silver Aero Precision .308 Winchester Bolt Carrier Group (MPN:APRH100185) features:
No Aero 'A' Logo
Machined from 8620 Tool Steel (Carrier) and 9310 Steel (Bolt)
Nickel Boron coated
Bolt is machined from 9310 steel
MPI
Forward Assist serrations
Weight: 17.92oz