That is actually a Befco flail mower. Serves double duty as counterweight so long as I am not in tight spots. I do have a weight box that I use for the grunt projects.
This idea and information motivated me to rig up ROPS lights for my Massey. Since the 2" magnets come in a set of six, I decided to just use two 2" magnets for each lamp which gives a wider footprint and more magnet-rops contact. I just used some metal strap I had to create the base as shown in...