The FailZero M16/M4 Bolt Carrier Group is a full-auto profile replacement BCG designed for AR-15 and M16 pattern rifles.
- Part Type: Bolt Carrier Group (Full-Auto Profile)
- Compatible Firearms: AR-15, M16, M4 (Mil-Spec)
- Material: 8620/9310 Steel
- Finish: Nickel Boron Coating
- Installation: Drop-In
- Includes: Assembled Bolt Carrier Group (Carrier, Bolt, Cam Pin, Firing Pin, Retaining Pin)
