Features ■Heart Rate Measuring range: 30bpm~300bpm Accuracy: ±2 bpm or ±2%(select larger) ■SpO2 Measuring range: 35%~100% Accuracy: 70%~100% ,±2% ;<70% unspecified ■Pulse Rate Measuring range: 30bpm~250bpm Accuracy: ±2 bpm or ±2%(select larger) ■Regular stethoscope ■Compact and portable,easy to use ■Display of ECG waveform, heart rate,SpO2 ,pulse rate ,pulse waveform ■Adjustable screen contrast ■Alarm for SpO2 and pulse rate exceeding limits ■Low power consumption Specifications: ■Power Supply : ONE 3.7V Lithium Battery ■Display : 2.7" LCD ■Dimension: 87mm(L)×63mm(W)×19mm(H)