completely assembled, ready to install AR-15/M16 Bolt Carrier Group. Kit includes six critical parts that are treated with EXO Technology, a revolutionary surface technology that provides permanent dry lubricity, radically improves the performance of your AR-15/M16 and eliminates the need to apply oil or grease to treated parts for the life of the weapon. All Fail Zero bolts are MPI tested and live fire tested. They do not do HPT, as they feel live fire is a better test.
Caliber / Gauge- 5.56 NATO
Carrier Style- M16 / Full-Auto
Bolt Finish- EXO Nickel Boron
Bolt Material- Carpenter 158
Carrier Finish- EXO Nickel Boron
Carrier Material- 8620 Steel
Magnetic Particle Inspection- Yes