This is the Mares Smart Air Scuba Diving Wrist Computer Multigas Capable Dive Features: Takes Mares Incredible Smart to Another Level Now with Air Integration! The Perfect Wrist Computer for Any Level of Diving Simplistic Interface Design Doubles as Watch: Dual Time Zones, Alarms, and Calendar Customizable Audio Alarms Surface Interval Countdown and Residual Nitrogen Reset Advanced User Interface for Custom Presets Catered to Divers Needs New Software and Advanced Microprocessor for Improved Battery Life User Replaceable CR2450 Battery Battery Life of 100 to 150 Dives New LCD Segmented Display & Backlight for Optimal Visibility Scratch-Resistant Mineral Glass Lens Two-Button System for Easy Menu Navigation Current Depth, Max Depth, Temperature, and Bottom Time Display Visual Ascent and Descent Rates with Optional Alarms Altitude Adjustable Up to 12,100' (3,700 meters) Pre-Dive Planning Features Dive Log Transferrable to Computer: PC or MAC Firmware Updates Available Thru-Dive Link Maximum Operating Depth: 492' (150 meters) Algorithm: RGBM Mares-Wienke Imperial/Metric Display Memory Capacity: 95 Hours Operating Modes: Air, Nitrox and Free-Dive Fresh/Salt Water Measurements 3 Gases Ranging from 21% to 99% O2 Freediving Mode (apnea) w/Dedicated Alarms The Smart Air takes Mares incredible Smart to another level this time with air integration! Via an optional wireless transmitter. The computer can receive data directly from the dive tank, including tank pressure, and it's now multi-gas capable. All the great features of the original and more! The Mares Smart Air Wrist Computer has a sharp and clear display, perfect ergonomics and user friendliness and is an all-rounder capable of multi gas and free diving. Quintessential: representing the most perfect or typical example of a quality or class. What happens when you add the superior sharpness of segmented characters, clarity of a perfectly laid-out display, and top it off with ergonomic advantages of two buttons? You get Smart, probably the smartest computer on the market. Smart replicates the excellent display of the Puck Pro, adding an additional button, buttons are repositioned to the side, all packaged into a much slimmer profile. On the surface, adjust your nitrox settings or view your logbook with ease. Underwater, you can manage alternate depth information (top row), completely independent from the ancillary information displayed in the bottom row. Mares finished it with a two-color strap and unique design, making this the perfect companion for your time away from diving. "