■Stethoscope：electronic sensor ,three Stethoscope modes
  Heart:20～230Hz
  Lung:100～800Hz
  H&L:20～800Hz

■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)
 
Features:

■Compact and portable,easy to use
■Display of ECG waveform, heart rate,SpO2 ,pulse rate ,pulse  
  waveform
■Based on latest piezo sensor technology
■Earphone output and 16 steps volume adjustable
■Alarm for SpO2 and pulse rate exceeding limits
■Low power consumption

Specifications:

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