Are you talking about the wrap bars?
Looks good except a wrap bar of that design with the bar above the spring relies on the spring to be rigid in compression, which it's not.
I'm sure it works to some extent, but I don't think it's ideal.
That's a variation of a bar that's been on the market for years. There's even a kit available through J.C. Whitney that does the same thing for pickup trucks - bolts with a bracket to the u-bolts and with a heim eye to attach to the spring shackle bolt. The ones I've seen have rubber/steel where this one looks to have used a spring hanger. That rod even looks a lot like the one that comes in the kit. It was around $69. a few years ago.
Doesn't work all that well because all it really is is a glorified spring helper that stiiffens the rear half of the spring. Get one made for a truck with cabover camper, it'll be cheap.