The FailZero FZ M16/M4 Bolt Carrier Group is a completely assembled, EXO coated bolt carrier group designed for M16 and M4 platforms, featuring a hammer and a Nickel finish for enhanced wear resistance and corrosion protection. Built to deliver smooth, reliable cycling, this bolt carrier group leverages FailZeros EXO Nickel Boron coating to reduce friction, simplify cleaning, and extend component life under demanding field conditions. The M16 carrier, semi-auto hammer configuration, and robust construction are engineered to support consistent lockup and dependable operation across repeating shoots, whether youre dialing in precision at the range or managing rapid follow-ups in dynamic environments. With its basic kit setup, it provides a straightforward upgrade path for shooters seeking improved corrosion resistance and easier maintenance without sacrificing balance or compatibility. The combination of a fully assembled design and precise finishes translates into fewer parts to assemble and a streamlined upgrade process, letting you focus on accuracy and shot cadence. This bolt carrier group pairs well with standard upper receivers and a variety of upper configurations, delivering reliable performance where it matters most.