Pocket BF-530 can display all working information on the LCD,including FHR,battery power volume,indicating signal of fetal volume and adjust the data and time; Built-in rechargeable battery can work continuously more than 4 hours; White backlight LCD display FHR and curve; Only 270g,with a belt to carry it conveniently; Automatically turn-off function (1 minute)can save battery power; RS-232 port can transmit signal to exterior computer