How would you ever back up this double swivel thing up? Is the pup fifth wheel trailer hard connected to the receiver hitch?
I’ve seen 5th wheel pin boxes intended for short bed pickups that lock the pin orientation relative to the truck bed and then swivel at the top of the box between it and the bottom of the trailer. If you lock the pin to this trailer and lock the pin box to the fifth wheel, it’s only got the one joint so you can back up, but it’ll drag one set of wheels pretty badly at any significant angle. Edit: after looking closer at the picture, I think they went the other way. It looks like the pin trailer has little or no ability to rotate relative to the truck frame.
I went to Automated safety hitch to check this out. Wow they are expensive. Since it pushes the trailer farther back I would think that aerodynamic drag would be a little higher
Four..! Hundred...! kilometers...? Fake out. Wonder when a kit like that is coming for the old Sprinters. There sure are a LOT of motorhomes based on those.