Nickel-Boron Coating Resists Wear & Corrosion
AR-15 firing pin features proprietary NiB-X® coating that gives superior lubricity, corrosion-resistance and surface hardness of Rc-70. Fits all standard AR-15s.
AR-15, Issue:11, Page:040
Big Book Catalog, Issue:72, Page:048
SPECS: Steel with Nickel-Boron coating.