Franklin Armory Ar-15 Bolt Carrier Groups come in the following calibers:
*Carrier machined from 8620 Steel
*Properly staked gas key
*Franklin Armory logo included
*Treated with Salt Bath Nitride
*Bolt Machined from 9310 or 158 Carpenter steel (depending on availability)
*Includes Extractor "O-Ring"
*Stainless Steel Firing Pin