The Reliability Enhanced Bolt Carrier Group is a 5.56mm full-mass, full-auto-rated M16/M4 bolt carrier group manufactured in Geissele’s state-of-the-art facility in North Wales, PA. The carrier features a properly torqued and staked, Chrome-Lined, Nanoweapon-coated gas key. The cam pin is machined from H13, an advanced tool steel also used to produce medical instrumentation. It is then coated with Nanoweapon (Chrome-Nitride) for maximum corrosion and wear resistance. The extended upper rails on the carrier also provide much greater stability and dramatically increase feeding reliability. The carrier is coated with Nanoweapon for maximum corrosion and wear resistance.