Features:
1.Compact and portable,easy to use
2.Display of ECG waveform, heart rate,SpO2 ,pulse rate ,pulse  
  waveform
3.Based on latest piezo sensor technology
4.Earphone output and 16 steps volume adjustable
5.Alarm for SpO2 and pulse rate exceeding limits
6.Low power consumption

Specifications:

1.Stethoscope:electronic sensor ,three Stethoscope modes
  Heart:20~230Hz
  Lung:100~800Hz
  H&L:20~800Hz
2.Heart Rate
  Measuring range: 30bpm~300bpm
  Accuracy: ±2 bpm or ±2%(select larger)
3.SpO2
  Measuring range: 35%~100%
  Accuracy: 70%~100% ,±2% ;<70% unspecified
4.Pulse Rate
  Measuring range: 30bpm~250bpm
  Accuracy: ±2 bpm or ±2%(select larger)

5.Power Supply : ONE 3.7V Lithium Battery
6.Display : 1.8" color LCD
7.Dimension: 88mm(L)×60mm(W)×18mm(H)