1. Usage FD-800D ultrasonic fetal doppler meets the fetus daily check and routine examination at home, clinic, community and hospital. 2. Features ? Easily and convenient operate ? High-fidelity, crystal clear sound ? Earphone and speaker are feasible ? High sensitivity water-proof probe ? Display with backlight LCD ? Unique ergonomic design ? USB functions to transmit data ? Flexible menu and parameter function ? Both audio and voice alarm ? Multiple work modes 3. Technical Specification ? Ultrasound frequency: 2MHz ? Ultrasound intensity: <10mW/cm2 ? Power supply: DC Ni-Mh rechargeable battery AC 220/110V, 50/60Hz ? Dimension: 220mm×220mm×140mm ? Display: 65mm×50mm LCD ? FHR Measuring range: 50~240bpm ? FHR resolution: 1bpm ? FHR accuracy: ±1bpm ? Power consumption: <12W ? Printing paper size: 50mm ? Weight: 2.1Kg