This is a billet RPR/American Firing Pin Back or cocking piece developed by AD Arms in response to the breakages many have experienced with the factory MIM part. This is designed to be a direct, drop in replacement for the factory piece which will not be susceptible to the typical breakage.

Machined from a solid, pre-hardened 4140 alloy billet, this is then nitrided for increased surface hardness, wear resistance, corrosion protection, and to provide a deep black color. This fully machined part will get the job done without risk of failure.

Furthermore, this part is lighter than the stock part so it can also increase lock-time performance all while being harder which decreases cocking effort.