This Dive Watch Gauges Depth by Letting Water In
The Rolex Deep Sea-Dweller, the Submariner's beefier older brother, is considered by many to be the classic dive watch. Mechanical, precise, aesthetically pleasing in a brutal sort of way, these sorts of watches set the standard. As any diver knows, knowing the precise depth is imperative to safe diving. While a few diving watches do combine the two instruments into one super-dive watch, the Oris Aquis blends the classic dive watch and the depth gauge in a completely unique way—by actually allowing water in.
Instead of relying on the ocean's immense pressure to push against the case (moving a lever to a marker indicating depth), you read your depth on this watch by seeing how far the water has compressed the air in the sapphire. With the depth measurements from 0 to 100 meters on the perimeter of the sapphire, it's pretty easy to see how far down you are, though the exponential nature of pressure and depth mean precision suffers the further down you drop.
Sturdy-looking, massive ("this is a very heavy watch," Hodinkee writes), and a marvel of functional and utilitarian style, there's little not to love about the Aquis. Unless you have tiny wrists.