... Battery Status and Voice Indicat portable Ultrasound doppler Pocket Fetal Doppler Ultrasound doppler Pocket Fetal Doppler Details: Fetal ... ,100mm,200mm)Valid area of ultrasound398±2mm²Ultrasound Intensity<5mW/cm² FHR MeasuringRange30-240BPM(Beat ... hoursOthersMeasuring ModeMean, Average, Continuous, BacklightDisplay3 digital FHR,Battery low,Voice,Ultrasound frequency,Mode typeButtonON/OFF, Voice Control, ...