This Bolt Carrier Group (BCG) comes fully assembled and ready to drop into most mil spec M16, M4 or AR15 upper receivers.  All critical parts are coated with EXO Nickel Boron technology that provides permanents dry lubricity, extreme durability, increase wear and corrosion resistance.  Our patented Nickel Boron coating will reduce friction and improve the overall performance of your rifle.
EXO technology eliminates the need to apply oil and/or grease to treated parts for the life of your weapon.
Nickel Boron treated parts include:

Bolt & Extractor (5.56 and .223 compatible)
Full-Auto Carrier
Full-Auto Hammer (single stage)
Cam Pin
Carrier Key
Firing Pin