Feature:Pocket Fetal Doppler mainly applies to detect the fetal heartbeat rate from the twelfth week; LCD can display FHR data and heart rate graphics, battery indicator, volume of sound and alarm indicator; Built-in rechargeable battery can work continuously more than 4 hoursTFT  LCD display for use conveniently at night; Automatic power off (one minute), self-detect function and alarm function when FHR is out of the normal range or battery power is in shortage; Only 270g, can be carried with conveniently with an earphone, gllus and portable handbag; Built-in speaker, collocate with earphone jack; 1.0MHz probe,optional 5.0MHz probe for blood stream. Specifications:Executive standard: EN61266: 1995 Ultrasonic frequency: 1.0MHz±10% Working mode: Pulse Ultrasonic Doppler Ultrasonic intensity: ≤10mW/cm2 Comprehensive Sensitivity: ≥90dB FHR range: 60--210bpm(±2bpm) Isptp: ≤0.1MPa Battery: 9.6VNi-MH rechargeable batteries Adapter input voltage: AC 100--240V 50Hz/60Hz Rechargeable battery input voltage（no load）: DC 5V/1A Maximum audio output intensity: ≤0.5W Doppler frequency: 100--3000Hz Static continuous working time: ≥4h Automatic Dormancy time limit:1 minute Working temperature: 10-40℃  Humidity: ≤80% Atmospheric pressure: 86--106kPa