1Rapid and accurate measurement of oxygen saturation of pulse rate and arterial hemoglobin level. 2Accurate determination of your oxygen saturation (blood oxygen saturation level), rapid oxygen saturation reading, pulse measurement, and convenient display. 3Compact and light weight, easy to carry, suitable for various finger sizes. 4Display: Blood oxygen SPO2 value, pulse PR value, blood oxygen bar graph, pulse waveform, PI (perfusion index), respiratory rate monitoring parameter (130R), sleeping: monitoring parameter (131R). 5Blue and yellow display screen, 5 level brightness can be adjusted.