1.Lightweight for carrying and Easy-To-Use.2.Manually adjust the direction of interface.3.OLED display , simultaneous display for testing value and plethysmogram.4.Real-time spot-checks.5.Low battery voltage indication.6.Sleep monitoring function.7.Datas storing and data analysis function.Specifications Sleep monitoring time: 8 hoursDisplay direction: OLED blue and yellow two-color display, 6 display modes, 4 display directions1. Display Type:OLED display2. SpO2 Measurement range:70%~99%Accuracy:±2% on the stage of 80%~100%;±3% on the stage of 70%~80%;Below 70% no requirementResolution:±1%3. PR:Measurement range:25BPM~250BPMAccuracy:±1BPM or ±1%(the larger one)4 PI index:measurement scope:0~20 (optional)5 Power: 2 AAA1.5alkaline battery6 Power consumption:below 30mA7 Automatic power-off:the product shuts off by itself when no finger is in the product >=8 seconds9. Operation Environment:Operation Temperature:5C~40CStorage Temperature:-20C~55CAmbient Humidity:15%~85% non-condensingDevice dimensions:64mm*38.8*35.5