The ST10ST tang sight staff only is made to replace the windage staff on the Red River Soule sights when going hunting and having concerns about possible damage to the Soule target sight. This stem has a vernier scale on both sides, without numbers. This stem will fit on the base of your Red River Soule sight having the detent wheel. You will have to cut a little detent notch in the bottom of the staff to engage the spring on the base. The notch does not have to be deep and should be made with a triangular file to form a shallow V. Start out by making a shallow V and keep deepening it slowly until the staff sits in the detent positively.