Features ■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 ■Earphone output and 16 steps volume adjustable ■Alarm for SpO2 and pulse rate exceeding limits ■Real-time detecting, TF card data record and review ■Recorded data can be transferred to a PC ■PC analysis software ■Low power consumption Specifications: ■Power Supply : ONE 3.7V Lithium Battery ■Display : 2.4" color LCD ■Dimension: 110mm (L) × 60mm (W) × 14mm (H)