AWOL:
No, I meant automotive ultrasonic parking sensors.
It seems to me they'd have to be at least a little moisture resistant.
there are 2 types of commercial parking sensors:
ultrasonic sensors --> made from "speakers" and they have no big protection (because any significant protection would block the sound)
and
IR sensors (IR diode, and IR reciever) can be behind a glass or plastic --> and that thin plastic layer makes them "moisture resistant"...
but, if the moisture blurs the thin plastic layer, the sensor will stop working, and you will have to wipe the thin plastic in order to get it working again