German Reibzündschraube variant ?

[MINENAZ16]

Hello,
This german igniter seems to be made of steel (rust).
I only know brass model.
I assume a variant. Any info ?

 

[Alpini]

They are common in steel, I wonder that you didn't notice them before.

 

[doctor]

The Projector tube 18 cm was fitted only with this steel igniter (electric) 'not same design as bronze type)
Steel pull igniters like design Bronze type always exist (not using for projector)