Garmin Descent Mk1 Watch-Sized Dive Computer Gray Sapphire with Titanium BandWhether you dive with or without tanks, in saltwater or freshwater, breathing nitrox, trimix, or holding your breath Descent Mk1 is the intuitive, do it all dive computer youve been waiting for. Its the first watch sized dive computer to offer surface GPS navigation with full color onscreen mapping and location reference so you can easily mark your dive entry and exit points. Once underwater, the proven Bhlmann ZHL 16c algorithm makes sure youre