Prowave 400sx160 ultrasonic transducers open type aluminium housing prowave 400st160 this ultrasonic ceramic transducer is an open type transmitter that come in a robust aluminium housing applications include remote control data transmission doppler motion detectors robotics intruder alarms energy saving devices etc a matched receiver is also available see 35 0180 prowave 400sr160 40khz aluminium ultrasonic receiver open type