Callem buck

Idk, but kinda looks as if it could be somekinda bolt release. It is interesting, would like to know myself

Hi, just bought a stoeger m3500 its been cleaned. My son and me was trying to pattern it and had to hold it 1' low and 1' to left, i went to pull choke and noticed choke off center. What to do? Other than that has been a great gun.