Ratio FreeDiver Helium-Safe 1000M Sapphire Automatic 1068HA96-34VA-BLK Men's Watch It will work if you take it with you under water and live there in a dry, pressurized environment for up to several weeks. At other times, you can use it for beachside funs and recreational water sports. You get to solve two purposes with just one watch. No, that’s three; for you’ll also be wearing it on a regular day at the city.