"Bloated" stainless steel radiator

There is a technique to inflate welded sheets with compressed air, which has been used to make various pieces of furniture. Among other things, for example, this stool: Using the same method, someone made radiators that I saw online a few months ago. As sometimes happens: I didn't remember it and now I can't find any information about it anymore.. Does anyone know it?

These?

Search for Oskar Zieta and furniture, he has a lot of things there.

It wasn't him, but I'm interested in everyone who does something like that ...

The furniture manufacturer (as far as I know there is only this one) is the one I meant as an example for the manufacturing method.
But he probably hasn't developed any radiators so far.

But he apparently hasn't developed any radiators so far.

Why would anyone want to do this nonsense with a radiator?

Sounds highly inefficient. But for example, the shown stool is more for looking at than for using.