H10-3 Pocket Fetal Doppler ( LCD Display ) It's used for detecting the fetal heart rate(FHR) at hospital,clinic,family. ? Easy to use ? LCD display ? Built-in speaker ? Blue Backlight ? Audio output ? Automatic switch-off ? Real-time and average ? Battery energy Indication ? Sound alarm function when FHR is out of the normal range ? Multi-colour of main Specification: ? Ultrasonic Frequency: 2.5 MHz ? Dimension?100(L)* 30(W)* 135(H)mm ? Weight : 0.5kg ? Continuous work time: 8 hours Configuration: 3.6V rechargeable battery?Charger?Manual