A while back at the range I lost my rear site but did not know it. When I was cleaning up for the day a saw this part on the table. I did not know what it was. I called Ruger and they sent me a new site free. I was looking at the Shop Ruger site and they had this part listed as a Firing Pin Blocker. I kept the part and today I took off the site and dropped in the part. I dry fired it and it all seem well. Does anyone know that this part does?