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. The upgraded bolt catch is 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. Comes complete with roll pin. Note: A mil-spec bolt catch spring and plunger are required for assembly and are NOT included. If the BC-PRO Bolt Catch is replacing an existing mil-spec bolt catch, please use care when disassembling the component from your lower receiver as you will need these parts to install the BC-PRO. Compatibility with other billet AR-15 upper & lower receivers is unknown. The BC-PRO functions with Forged Receiver sets and Raven, Onyx Receiver Sets. FeaturesPreci...