Mine is almost a twin that I've had and used for over 12 years. It has a piece of wood with leather on the inside screwed to the left side and the right side has a piece of 3/8 metal with leather on it on the right had side. The metal has a hole where the screw for tightening, there is only one on mine, will enter a bit. It has a narrow "U" shaped piece cut out on each sides opposite. This will allow you to slide pieces, blades, etc., over on an angle as well as being able to turn the box 360. Frank