I received this Helvetia watch in a batch from the united kingdom. It didn’t run too badly, however, it did have an amplitude on the lower end and it was nearly one minute slow. Also, the movement itself was filthy. A few very little hairs and dust particles. Finally, it seemed like it’s been previously over oiled. Little puddles of oil were on the base plate and underneath the barrel bridge.
The movement is the in-house Helvetia 64. A hand winder with 17 jewels. It’s a 13’5 ligne movement so it’s rather big for a vintage watch. I’d date this Helvetia watch to the 1950s.