One-click measurement of blood oxygen saturation (SPo2), pulse rate (PR), perfusion index (PI) and other important human health indicators. Destructively measure the heart rate variability index—RRI. The mobile terminal app displays data, tracks, and predicts data trends. It can also be accurately measured during exercise and low blood flow. Passed CE, RoHS, FCC certification to support medical device certification in other countries or organizations. Small size, low power consumption, easy to use and easy to carry. The silicone shell and soft finger contact material are comfortable to wear