The Mares Smart Apnea (Free-Dive) Wrist Computer is an astounding new wrist computer for the most advanced free divers and spear fishermen. The Smart Apnea does not contain Scuba diving algorithms and is designed for free diving only. With that in mind, Mares has constructed the perfect dive watch that caters only to the needs of free divers. This makes the Smart Apnea one of the greatest wrist computers on the market today for free diving and spear fishing. A new LCD segmented display and scratch-resistant mineral glass gives you optimal visibility in any condition. With the brilliant new display of the Smart Apnea you will find interface navigation extremely easy. New software and an advanced performance microprocessor make managing and accessing each option very intuitive. Featuring a simplistic two-button system you can access instant depth information, dive time, water temperature, descent and ascent speeds, recovery time, plan mode, audible alarms, residual nitrogen reset, altitude adjustments, and dive history. Audible alarms can be customized to sound in situations like: depth, time, and recovery, speed, and hydration reminders. The new Smart Apnea features modes such as free diving, bottom timer, countdown timer, training modes, and surface mode. Surface mode allows you to wear the computer as a stylish, everyday watch. Free dive mode allows you to access the features mentioned above, as well as access the computer expanded dive memory bank. It will allow you to store up to 9 sessions with reading and data sampling every second. The data stored for each individual dive is easy to access and review. This allows for precise planning of your free dives for recreation, competition, or training. Dive history can also be easily uploaded to your PC or Mac computer for cataloging and view via the Mares Dive Link USB. You can also download updates for firmware as they become available. The Mares Smart Apnea is rated to 492′ (150 meters). The battery will last up to 200 hours of diving and is user replaceable. The batter indicator on the screen will warn you when battery levels are low. The Mares Smart Apnea is one the most versatile watches on the planet and outside of scuba diving haves you covered in every aspect of diving, dive training, and everyday use. The Smart Apnea is your next and only watch. The Mares Smart Apnea is powered by a user replaceable battery, is altitude adjustable has dual time function and back light for low light conditions.