QPQ, or Quench polish quench, is a specialized type of nitrocarburizing case hardening that increases corrosion resistance.
Coating: Black Nitride
Bolt carrier material: 8620 steel
Bolt: 5.56/.223 Right-Handed Bolt assembly
Included parts: Bolt carrier, bolt assembly, cam pin, firing pin, and firing pin retaining pin
Design: M16 carrier with a shrouded firing pin
Staking: Proper mil-spec staking of the gas key
Fully compatible with any brand mil spec upper receiver, not just StagSA240015
