Fetal doppler , new developed model of our product sonotech m, with large screen and fhr wave form and thermometer (c&f). Features : *easy to operate *tft large display: *fhr (digits) *fhr wave form *battery indicator *speaker volume *fetal heart beating rhythm indication *high sensitive transducer *accurate fhr and the same advanced fhr algorithm with that used in fetal monitor *aa dry battery or rechargeable battery acceptable *automatic power-off when no signal or no operation *built-in speaker *output for headphone *weight: about 245g (including batteries) *come with high quality & comfortable carry case