Specifications: 1.Display mode.OLED Display of oxygen saturation:70~lM%,±2%Pulse power display:25~250BPM,± l%or±lBPM,and take the large one 2.Power supply:2 AAA 1.5V alkaline batteries,Voltage suitable range:2.6~3.6V 3.Power consumption:less than 30ma 4.Measure precision:the oxygen saturation between 70%-99%,the precision is ±2%;and less than 70% the precision has no definition;the pulse power is ±1% or ±lBMP,and take the lager one. 5.Measure capability under the situation of weak perfusion:it can rightly display the oxygen saturation and the pulse power when the pulse fullness degree is 0.6%. 6.Compared to the measure value in the darkroom,the oxygen saturation in the natural light and the illuminate light-house,the wap is less than±l%. 7.Have function switch, and it will stop automatically after. 8.seconds without finger insert in.