Thats a flywheel from a sit down exercise machine. I bolted it to the hitch with washers and kept it on there when I had a blade on the front and plowed the sidewalk. It came off a few times. That tractor has been taken apart but I kept the old cast iron wheel weights that are sandwhiched between the wheels. I think I have all of the threaded rod used also. I'd love to do this with my Toro 266-H.