The CHOICEMMED MD300C21C portable pulse oximeter is designed to measure heart rate (simply put, pulse) and blood oxygen levels. All of these indicators are extremely important for athletes, people undergoing oxygen treatment, and physicians whose patients are under anesthesia. The CHOICEMMED MD300C21C pulse oximeter is finger mountable, runs on two AAA batteries and provides all information in 6 modes, including the ability to display a heart rate histogram, which is sure to be appreciated by professionals. The large color LED display can be customized with 10 brightness levels and the automatic 8-second shutoff after removing the pulse oximeter ensures efficient use of batteries. The device looks great and has a lanyard to hang it from, so it won’t get lost!