The Element II can be operated as an Air computer, Nitrox (EANx) computer, digital depth gauge/timer or as a free dive depth gauge/timer. The IQ-750 offers several desirable features including: Water-activation, 2 Mix Gas Switching ability, a large alphanumeric and backlit display, audible and visual alarms, advanced user safety settings, and PC download/upload. In addition to offering the latest comprehensive computer features, the IQ-750 adds a Deep Stop function for enhanced safety. Deep Stop Function Several TUSA computers feature an optional deep stop function for additional safety. The deep stop mode is activated when a dive exceeds 80 FT (24M) for more than 1 second. Upon ascent, the computer will display a Deep Safety Stop screen and the recommended stop depth for a period of 2 minutes. This deep stop is highly recommended as additional opportunity to off-gas, but is not mandatory. If the diver chooses not to serve the stop it will not adversely affect the remaining No-Decompression Limits of the dive. Features: Advanced 3 button puck-style module in wrist boot. Air, Nitrox, Gauge, Free Dive Operating Modes. 2 Mix Switching Feature: Mix 1 (Air, 21-50%), Mix 2 (Air, 21-100%). Manual or Water-Activation. Audible and Flashing Icon Alarms. Large alphanumeric and backlit display. Advanced user safety settings. Deep Stop Feature and Safety Stop. 1 Touch Log Access. Automatic altitude adjustment from sea level to 14,000". No fly icon, residual nitrogen discharge time display. PC download and upload settings/log data with TUSA Datalog Interface. User-replaceable battery with hot-swap (Battery: CR2450, 3V). TUSA Algorithm based on Buhlmann ZHL-16c. Variable Ascent Rate Indicator.