• 8620 steel full-auto carrier : heat-treated, hard-turned, and ground for exact mil-spec tolerances
  • Carpenter 158 or 9310 bolt : shot-peened and hard-turned to ensure superior durability
  • Quantum Peak Quench (QPQ) nitride finish : increases corrosion resistance and reduces friction
  • Lantac CP‑R360 domed cam pin : CNC-machined 17‑4PH stainless hardened to H900 for smoother cycling
  • Magnetic Particle Inspected (MPI) : verified crack-free for safety and reliability

Full details and secure checkout: https://3crtactical.com/lantac-ar-15-black-nitride-milspec-bolt-carrier-group/