You just need to insert a finger into the photoelectric sensor for diagnosis, then the large OLED display will clearly show the result. Either you can put it in the bag or you can hang it in your neck or wrist with the supplied lanyard.
Pulse Oximeter UK| CE 0123 Certified| OLED Display| Fingertip Oxygen Saturation Level Monitor for All Age Group| Accurate Fast Result & Easy Reading| Portable Instant Measurement
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