The chemicals in cigarettes can cause false readings with some pulse oximeters.
Make sure the battery is fully charged before you use the unit for the first time.
Change sensor site and check skin integrity, circulatory status and correct alignment at least every 2 hours.
Light passes through the finger If your finger was not in the pulse oximeter, the light would easily travel from the generator to the detector.
In case that the personal collection is not possible, the customer needs to appoint a representative to receive the good on behalf.
We look forward to assisting you.