Oceanic OC1 Air Integrated Dive Computer with Transmitter & USB PC Cable Precision Digital Compass including North, and reference modes and declination adjustment Digital Watch, Air, up to 3-mix Nitrox, - Gauge and Free Dive Modes - Max Depth 660ft / 200m Dot Matrix Display provides superiority readability and intuitive user-interface Switch between 3 independent transmitters, with up to 3 Nitrox mixes to 100% O3 Advanced watch functions include: Alternate Time Zone, Stopwatch, Lap Timer, Daily Alarm, and Countdown Timer