Below is tech spec:
Performance Index

SpO2%

●Measurement Range:  0 ~ 100%

●Measurement Accuracy: ±2 %
●Measurement Accuracy: ±2 % at 70% ~ 100%    No indication at 0% ~ 69%

Pulse rate

●Measurement Range: 30 BPM ~ 250 BPM
●Measurement Accuracy: ±1 BPM or ±2%  whichever is greater

Probe type

●LED red wavelength: 660nm  

●LED infrared wavelength: 880~940nm

Environmental Requirements

Temperature Range:

●Operating:  (-10 ~ + 40)°C

●Transport/Storage: (- 40 ~ + 55)°C

Relative Humidity (noncondensing):
●Operating: 0~93 %

●Transport/Storage: 0~95 %

Power Requirements

●Battery: Four standard  AA size rechargeable

●Ni-MH batteries are applied on GB,Input voltage: 00~240V AC 50/60Hz,

●Input power:14VA

Continuous operating time

●Internal power operating time: ≥10h