Since I saw one of these on eBay today I searched the forum and realized I had never posted on this model. So, here it is!

Near as I can guess, this watch was from around 1950. It was used to time something for less than 60 seconds. The top pusher stops the seconds hand until you release pusher and it starts going again, the bottom pusher makes seconds hand go back to the 12.

I actually have two of these watches. You don't see them come up on eBay often and the timing parts are just about impossible to find today. One or two other watch brands had this type of watch and I have seen even fewer of those over the years than I have of the Zodiac Stop.