These are custom Fail Zero Extreme Nickel-Boron coated bolt carrier groups
The carrier is made from 8620 steel and includes an installed and properly staked gas key.
The bolt is an AR15 Performance Nickel Boron Super Bolt. These bolts are strong!
There are full auto bolt carriers and are legal for use in your semi auto AR15.
These carriers are nickel boron by Fail Zero.
All small bolt parts are top shelf from a name brand supplier.
The Nickel Boron finish on these carriers provides a shiny chrome like finish. It resist corrosion, is very easy to clean, provides increased lubrication, reduces friction, resist wear and provides cooler operation.