The first, as far as I know, diving watch with a mechanical depth gauge, made in 1964. The more famous other one was the Favre Leuba Bathy 50, made in 1966. The Favre Leuba Bathy 50: How thrilling are these vintage watches. Best, Nicolas ...
I am not familiar with vintage watches, but here you post two interesting peaces. The Nivada Grenchen Depthomatic is uber cool. Sure, the Leuba is great too.