Features: 
Safe to use at home without radiation, all in one design 
Two audio output can connect with headphone or the recording cable to make a permanent memorial for the baby
Can record mother's heartbeat, pacify baby no crying
User friendly design, small and compact, high sensitivity, easy to operate
Specification:
Utrasound frequency : 3 MHz
Power: 9V dry battery
Dimension: 105*70*50mm
Machine N.W.: 0.1 kg
Storage temperature: (-10~+40)°C
Shipping method: Air, Sea, Road