I would say weight....it appeared to be almost solid steel. At the minimum, it was heavy welded plate construction.
Or possibly, it is not attached yet, and they only have the safety chains hooked up at the moment. I never saw it in use /forums/images/graemlins/frown.gif.
That is a huge blade. If I were able to actually stand there and look, and then seeing all that land, even that blade would look small. /forums/images/graemlins/shocked.gif Do you remember what model those Cases were?