... monitoring situations, or using in home.It has a large LCD screen display the FHR, and an audio output port connected ... .FEATURESLightweight and portable, Easy-to-useLong life design, dust proofLarge backlight LCD display FHRBuilt in Hi-Fi speaker, clear fetal heart beat ... 60-210BPM time/minuteFHR resolution 1BPMFHR accuracy ±1BPMDisplay 45×25mm LCD,3 bit FHRAudio output 0.5WAuto-off 2 minutesBattery 9V ...