I saw this on a friends ZD 326 Kubota mower. I always wanted a way to pull my fertilize spreader, aerator, and other small implements behind my zero turn.
2009 Kubota RTV 900, 2009 Kubota B26 TLB & 2010 model LS P7010
I guess he needed some extra weight for traction. No need for it to be that strong otherwise. I used a piece of scrap 1/4" thick x 3" or so wide for mine. I just bent in in an L shape and bolted it to the existing crash bars in back. It works great for pulling a fertilizer distributor and leaf sweeper and even to hook a tow strap in to pull the ztr out of the mud with my RTV when I get too close to the pond.
Heck, 1/8" material would be strong enough for anything a zero turn would pull.