I recently received this 1930s Helvetia sports watch from Germany. I couldn't say no at the price it was going for.
It's small, as is usual for the period, at 28mm and it needed a bit of TLC, as can be seen from the sellers picture below, but cleaned up I think it's very nice. Serial number dates it from 1938. Black dials seem to popular in Germany.
Just needs a service now.
For more information on Helvetia 1930s Sports Watches check out the link in the menu under 'Watches'.