Hello. I had a question to ask. On the Remington 1100 shotgun there is a small brass pin about 3/16ths - 1/4 inch in diameter on the left side of the forearm just to the rear on the tightening knob. It is only on the left side of the forearm and it does not go all of the way through the forearm (and out the other side). I can not figure out what that is for. When I look as the 1100s on the website, there is no specific type of gun that has these. So, I am asking, what is that small brass pin for? Thanks for any replies.