Men's digital quartz professional wrist dive computer. Nitrox features maximum PO2 warning (1.6 fixed). OTT (Oxygen Toxication Time) calculation and warning. Dive computer features: full decompression data, dive log memory, depth display and memory ( to 266 ft.), alarms for ascent, rate, depth alarm, maximum depth and all errors for Nitrox diving and more. Includes carrying case, charger, software and instructions. Communicates with Window(R) based PC.