Description Corometrcs 5700LAX Ultrasound Transducer Compatible fetal transducer for fetal monitoring, Corometrics Nautilus 5700LAX Corometrics 116, 118, 120, 128, 129, 145, 150, 151, 155, 170, 171, 172, 173, 174, 250, 259 and 340 monitors.