Easy To Use, High Performance Baby Heartbeat Monitor . New Moms can operate the Fetal Doppler by themselves to hear fetal heart sound and calculate FHR to realize the purpose of pre-monitoring and fetus caring. Equipped with a high definition color LCD display. One button to choose Data Digital display or Curve display interface. Easy to find the baby position quickly as early as 12 weeks, the best time for use is 16 weeks into pregnancy. Safe and Accuracy: High sensitivity probe, no radiation, low power, safe to baby.