LANTAC BC-PRO Upgrade Bolt Catch Precision CNC machined from 17-4 PH (Precipitation Hardened) Stainless Steel in H900 condition and QPQ (Quench Polish Quench) Nitride treated to AMS2753D specification for enhanced corrosion resistance and lifespan. No investment casting or MIM manufacturing. The BC-PRO catch features an aggressive grip texture enlarged paddle and supporting geometry that increases strength around the pivot hole area as well as allowing for easier manipulation of the bolt catch control itself.