art deco/ mid century chrome tubuler steel side chairs with pivoting backrest. Original green velvet/corduroy upholstery

Set of 4 art deco/mid century side chairs, chrome tubular steel frame construction. The chairs have unique backrests that can pivot right the way round, a feature I've rarely seen on dining chairs. Pretty sure its original 2 tone green velvet/corduroy upholstery in excellent condition.

I spent 2 days crosschecking my chairs with examples of every chair style ever made (more or less).
I could not fined 1 example of these chairs anywhere. The closest i have gotten is that its pretty much a Wegner CH36 style of chair produced in steel. And all my hours of searching the internet didn't turn up 1 such example, its got me stumped. So if any body can tell me any thing about these chairs i would be very grateful.

Thanks, A.