We are offering pocket baby fun fetal doppler.Brief introductionfd-200a ultrasonic fetal doppler meets the fetus daily check and routine examination at home, clinic, community and hospital. features1.easy and convenient operation2.high-fidelity, crystal clear sound3.earphone and speaker are feasible4.high sensitivity doppler probe5.low ultrasound dosage6.unique ergonomic design technical specification1.ultrasound frequency: 2mhz2.ultrasound intensity: