Hmmm. My 4720ch doesn't use chains. It uses one piece of square tubing placed inside a larger piece of square tubing with a series of holes and a pin that let you telescope it's length to limit the horizontal swing of the sway bars. Much simpler, easier to use, and more effective than the chains that are on my old Massey. I'm surprised that your 4720h uses chains. Do you want a picture of mine?