1. Usage FD-200A ultrasonic fetal doppler meets the fetus daily check and routine examination at home, clinic,community and hospital. 2. Features ? Easy and convenient operation ? High-fidelity, crystal clear sound ? Earphone and speaker are feasible ? High sensitivity doppler probe ? Low ultrasound dosage ? Unique ergonomic design 3. Technical Specification ? Ultrasound frequency: 2MHz ? Ultrasound intensity: <10mW/cm2 ? Power supply:Alkalinity battery ? FHR Measuring range: 50~240bpm ? FHR resolution: 1bpm ? FHR accuracy: ±1bpm ? Power consumption: <1W ? Dimension: 135mm×95mm×35mm ? Weight: 500g