Welded thinner 3”x1” square tubing. To box blade hoping to create a weak point to break if over loaded. Box blade and 3 point tractor should be protected. Great for moving trailers around land, land projects. If I was going on road I would put chains. Do at your own risk. I seen the county do it, and thought it was a smart idea. If and when trailer stuck in mud, or need to get a load somewhere on a muddy day comes in handy.