An Eagle Cap Camper Snapped A Ram 3500 Dually In Half, Mopar Refuses $17,000 Repair Bill

What size truck do you guys think that Eagle Cap is designed to be mounted on? With that overhang in the rear, and the water and toilet in the rear area (as someone suggested), I would think that sucker is too big for ANY 1 ton truck. If that's the case, what vehicle did Eagle design that model for?
I don't know what that camper was designed for, but my F550 chassis is twice as thick thru the middle as my 2500hd diesel pickup.
I would think it would need a 4500 or 5500 chassis. Think trucks with ten lug wheels....
It even looks a little too big for the F450 in the video above.