Now here is a one to ponder over. It's a Jean Bogard divers watch Swiss made. I picked this up s/hand in the late 80s for the cost of £24
I used it for my main diving watch for around 9 years till health grounds stopped me diving. It has been down to around 170 ft a few times with no issues.
I've never had the back open or had it serviced which is long over due. The case is 37mm across and keeps good time.
I've looked for that maker online but can not find them.