I found a lovely Helvetia watch and want to get it for my husband if I can verify it was made close to 1949. I need advice, after finding very little during my online research. The watch is manual wind. The dial is army green with Arabic numbers, "Helvetia", and "Waterproof" on the face. There is no separate box on the face for a second hand, I believe the second hand is attached centrally with the hour and minute hands on the face of the wristwatch.The arms look as though they would glow in the dark (perhaps coated with radium?) Inside the watch are the numbers: 9253575 (serial number?), 820B (movement?) and 16-14 (jewels or gold karat?) The external back of the case shows the number 3190.
Would someone be able to advise me, as to when when this watch was manufactured?