Quartz movement, Dive Computer Watch also sold sepratly is the Communication Unit model # CTZ0328NX, 02% settting (22-50%) by 1% increment, Maximum PO2 warning (1.6 fixed), OTT (Oxygen Toxication Time) Calculation and warning, Full decompression data, Dive log memory up to 100 dives, Depth display and memory current and maximum 266 ft, Alarms for ascent rate, depth alarm, maximum depth and all errors for nitrox diving, Water temperature display and memory, Dive start, finish, and elaspsed time memory, Depth and water temperature log, Water thermometer, Calculation of no fly time and residual nitrogen in the body, Measures surface interval, Automatic altitude adjustment, Battery power indicator, DCIEM decompression model, Fully automatic calendar, Alarm, 1/100th second chronograph, Countdown timer from 99 minutes to 1 minute, 12/24 adjustable display, World time, Destination timer, Backlight, 200 meters/660 feet water-resistant, Additional Features: (Communicates with Windows based PC, Transfer dive log data to PC via infrared port or USB with communication unit (sold separately), Transfer time, Alarm, Dive alarm and anniversary data (graphic) to another Cyber Aqualand Nx via infrared port, Display and/or print dive data and graph via infrared port or USB with communication unit (sold separately)).