Of course the original was made of wood. He just got it finished in the last week or so and has used it on several regular sized horses already. He’s got a couple of Hackney Ponies that he’s had in there too, so there's hope for Pony if you could get her down there. ;o) The shafts are a little high for them, but he fixed something up to keep them from ducking under. He says it’s virtually impossible for a horse to act up at all while in this rig. They can’t buck, rear up, lay down, kick or run off. They are strapped in and all they can do is go around and around. It has hydraulic brakes so he can increase the drag to make them work harder or stop them completely. He says that is works better than anything he’s ever used, including a ground slide and a wagon. He seems to think that the monotony of just going around and around makes their mind more open to training and makes them listen better. He can even sit on them while they are between the shafts so that they are used to that too.