Technical Parameters ■  Display Format: 64k color OLED        ■  Display Mode :Two Direction ■  Back light: OLED   ■  SPO2:35-99%   ■  Pulse Ratio:30-255 BPM   ■  Pleth Wave: OLED Graphic Display   ■  Battery Voltage Low Indication: OLED Bar Graph.   ■  Power Requirements: Two AA size 1.5V Alkali Battery;   ■  Power Consumption: less than 60 mA.   ■  Resolution: 1% for SPO2 and 1 BPM for Pulse Ratio. ■  Measurement Accuracy: ±2% in stage of 70%-99% for SPO2 ■  Unspecificed in stage of 35-69% for SPO2 ■  ±2BPM or ±2% (Select Larger)for Pulse Ratio. ■  Measurement Performance in Low Perfusion: SPO2  and  pulse rate ＆#118alue can     be shown correctly when pulse-filling ratio is 0.4%.   ■  Interference  Resistance  Capacity  against  Ambient Light :  Deviation  is  smaller  than  ±1% ■  It is equipped with a function switch, through which the Oximeter can be automatically powered off when no finger is in the Oximeter more than 4 seconds.