Oceanic Veo 3.0 Dive Computer Puck Module Powered by Oceanic's Exclusive Dual Algorithm&trade; - Your choice between Pelagic DSAT (Spencer/Powell data basis) or Pelagic Z+ (Buhlmann ZHL-16C data basis) Powered by Oceanic's Exclusive Dual Algorithm&trade; - lets you choose the decompression algorithm basis that best suits your diving needs without compromising safety 3 Operating Modes: NORM (Air and Nitrox), GAUGE (with run timer) and FREE (tracks calculations to allow switching between NORM and Free) 3 Operating Buttons with "Step Back" interface &#150; 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)