Product Features：
     1. Oxygen pulse sensor module (for communication format), allowed the researchers to pick their own self-
         designed embedded system or PC monitor screen and database.
     2. To provide oxygen and pulse monitoring software (which can automatically record the maximum range of 
         measurement time 60 minutes)
     3. Oxygen concentration measurement range: 35% to 99%.
     4. Heart rate measuring range: 30 ~ 250bpm.
     5. Oxygen concentration accuracy: 70 ~ 99% (± 2%), 35 ~ 69% (undetermined)
     6. Heart rate accuracy: 30 ~ 250bpm, calculate the 
         average pulse frequency of every 4 cardio beat cycle, the average error is less than 3%.
     7. Input Power: DC5V.
     8. Infra-red transmitting and receiving wavelength: 660nm wavelength of ~ 880nm wavelength.