FailZero

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...

High quality components and precise manufacturing make FailZero parts ideal for maintaining and upgrading firearms. The durability, reliability and excellent build quality of these parts will ensure...

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...