Features: * All to one design * Power with dry batteries (9V) * The probe taking the principal of fetal ultrasound to collect the fetal heart beat signals of fetus. * Function: 1. Acquire the fetal heartbeat signals from fetus, broadcast the fetal heartbeat sound through headphones or out with loudspeaker 2. Can be used singly and also transmit the fetal heart signal to the Remote Central Monitoring System in hospital through ordinary monitoring telephone to provide diagnosis for doctors, enjoying the hospital experts' diagnostic services at home. 3. Can transmit the real-time sound of fetal heartbeat to the computer saving for memory by specialized data lines * Characters: Small beautiful appearance, strong ability of processing fetal heart signals, invulnerable to outside interference Specification: * Utrasound frequency: 3.3 MHz * Acoustic intensity: < 10mW/cm^2 * Peak negative pressure: <1 Mpa * Output beam intensity: <20mW/cm^2 * Dimension: 21cm X 16cm X 8cm