CONTEC CMS50N Digital Color OLED Finger Pulse Oximeter SpO2 Blood Oxygen Monitor

(SpO2 error is ±4%, pulse rate error is ±2 bpm or ±2%, whichever is greater. 2) SpO2 and Pulse Rate display,Pulse Rate waveform and bar graph display. 5)Screen brightness adjustable. of man-made light or indoor natural light and that of darkroom is less than ±1%.

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