Unknown (roarer) burner

Hi, all.
I have acquired a Primus No. 1 stove (date code W= 1932) with a burner that I cannot identify.

Can anyone tell which it is? I find no markings on it.

I suspect it is not Swedish at all - possibly British?

 

What does the top look like?
Duane

 

The top is shown in photo no. 3 above. The centre "knob/button" is fixed to the rest, while there is an opening under/around it.

Sorry for the misleading orientation of the photos.
Håvard

 

Sorry, that looked like the bottom from a smaller stove when I did a quick look earlier.
Duane