Measures SpO2, Heart Rate, Pulse Intensity and Perfusion Index in one device. The compact and lightweight design allows you to carry it with you and stay healthy anytime, anywhere. You can take measurements before and after any exercise and monitor your body signal changes that occur. NOTE: This oximeter is for sports or aviation use only and is NOT intended for medical use. How to ensure the accuracy of your measurement? 1、Moving too fast will affect the accuracy; try to stay still while waiting for your reading. 2、When the oxygen saturator and the heart are at the same level, the measurement results are optimal. 3、 Avoid nail polish or long nails on the finger used for the reading. Fingers should not be wet at all either. 4、Ring finger, middle finger and index finger are recommended as suitable monitor position