ACCURATE AND RELIABLE - Consistently beat other pulse oximeter in terms of accuracy and reliability during clinical tests. PLETHYMOSGRAPH AND PERFUSION INDEX - Tells you if you are taking your SpO2 and Pulse Rate properly. No more second guessing if the readings are reliable or why the pulse oximeter is not giving you a reading. NEW SOFTWARE FEATURES - 1) Auditory alarm to warn you when your SpO2 and Pulse Rate are beyond set limits. 2) Auditory Beeps for every detected pulse. 3) Adjustable brightness. SPORT ENTHUSIASTS - Suitable for mountain climbers, skiers, bikers, aviators or anyone interested in measuring their SpO2 and pulse rate while on the move.You should only use the pulse oximeter before or after your exercise. Also, you must remain stationary while the pulse oximeter measure your pulse and SpO2 READY TO USE OUT OF THE BOX - Include 2X AAA BATTERIES and a LANYARD for convenience.