SpO2 measurement range:  0%~100%
Accuracy: 70%~100%: ±2%
 0%~69%: unspecified
PR measurement  range: 30bpm~250bpm
Accuracy: ±2bpm or ±2%, whichever is  greater.
Resolution: 
SpO2: 1% 
PR: 1bpm
Measurement Performance in  Weak Filling Condition: SpO2 and pulse rate can be shown correctly when  pulse-filling ratio is 0.4%. SpO2 error is ±4%, pulse rate error is ±2 bpm or  ±2%, whichever is greater.
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%.
Working current:  ≤30mA
Power supply: two “AAA” batteries
Safety classification: type BF  applied part