Kai kristiansen?  

Not Kai Kristiansen. They are made by DUX , but I don't know who designed them. Maybe an unattributed design from the company.

Ok so the way I understand Dux is that it was Folke Ohlsson's company and it was primarily an importer, not a manufacturer. A person on another discussion board said this picture was taken from the underside of his chair that is the same model as mine. Does this mean anything to anyone?

Dux actually was a manufacturer. Ljung Møbelindustrier in Sweden is more or less Dux. The Ljung family owned both is what I remember right now.
And that stamp is for Høng Stolefabrik. Høng was a kind of lower end company. Worked with Erik Kierkegaard, off the top of my head
see here:
https://www.bukowskismarket.com/en/533847-karmstol-hong-stolefabrik-danm...

Thanks Lief. As always I am impressed with your knowledge.

They are indeed Høng Stole:
http://www.lauritz.com/da/auktion/saet-paa-seks-spisestuestole-hoeng-sto...