Oceanic Geo 2.0 Air/Nitrox Computer Watch, White Band Slate Blue Face w/ Case Powered by Oceanic's Exclusive Dual Algorithm - Your choice between Pelagic DSAT (Spencer/Powell data basis) or Pelagic Z+ (Buhlmann ZHL-16C data basis) 4 Operating Modes: WATCH (Alternate Time, Chrono, Daily Alarm, Countdown Timer), NORM (Air and Nitrox), GAUGE (with run timer) and FREE (tracks calculations to allow switching between NORM and Free) User-Friendly Interface with "Step Back"  allows forward and backward navigation through menus and settings Switch between up to 2 Nitrox mixes to 100% O2 with no restriction (Gas 1 may be up to 100%, and may be less or greater than Gas 2) Includes Carry Case