Eliminate irregular rim indentation due to a blunt or improper firing pin. The KIDD Firing Pin made from a wire EDM machine replaces the tool and die process of stamping out the factory firing pin. This difference in production results is a much higher quality part for your rifle. FEATURES: Upgrade accessory for the 10/22 bolt Achieve consistent ignition Positive rim indentation Properly hardened steel Precision ground and wire EDM cut holding 0.0001" tolerance Installation Note: This compression spring is directional in nature due to one end being conical. When installing the spring be sure to keep the larger end of the spring toward the bolt face and the smaller end (conical) towards the rear. Packaging Includes: firing pin spring