Ultrasonic frequency: 2.0MHz±10%
Ultrasonic intensity: ≤10mW/cm2
Comprehensive Sensitivity: ≥90dB
FHR range: 60--210bpm(±2bpm)
FHR alarm range: ≤100bpm or  ≥160bpm
Isptp: ≤0.1MPa
Maximum audio output intensity: ≤1W
Doppler frequency: 100--3000Hz
Static continuous working time: ≥4h
Working temperature: 10-40℃ 
Humidity: ≤80%