Specifications: Color: Blue, Yellow Display Mode: OLED display SpO2 Measuring Range:0%~100%, (the resolution is 1%). Accuracy:70%~100%:±2% ,Below 70% unspecified. PR Measuring Range:30bpm~250bpm, (the resolution is 1bpm) Accuracy:±2bpm or ±2% (select larger) Resistance to surrounding light: The deviation between the value measured in the condition of man-made light or indoor natural light and that of darkroom is less than ±1%. Power Consumption:less than 25mA Voltage:DC 2.6V~3.6V Safety Type:Interior Battery,BF Type