Hello peeps

does anybody know what material was used on the anti-slip areas of the wing root walkways on the good old Ju 87?
I can't make this area out on any photos and have never seen a 1/1 aircraft!

On the model (Hasegawa 1/32) they are represented by three paralell raised lines that might be raised rubber blocks or similar. There are also some nice shiny decals that I don't really fancy on what must have been a well trodden area.

Thanking you in advance

Steve

I found a piccy where said strips look like aluminium bolted/riveted to wing surface. If anyone knows better would you let me know,please.
Cheers
Steve