It has the CRAFTSMAN logo so I assume its from Sears... You can see there are 2 knurled nuts on top of a plate with grooves in it it looks like it might hold some kind of tool but its spring loaded so it really doesnt clamp down on anything...Its setup to tilt up & down and move sideways... All of this was gathered just by looking at it and that all I have to offer ... If you need more pictures please let me know...