johnnydoom but the transducer is a very costly item to produce.
I'd be interested to know what they do there. I was an ultrasonics engineer and later salesperson. By themselves transducers are generally pretty inexpensive. It doesn't take much to generate a signal, but in this case it could be multiple frequencies or other things going on.
In some cases the medical industry just pays more. We used to have a sensor we sold to the food industry for $3, but we sold it to medical device mfrs for about $25. And there was no difference although the food industry did use a much, much higher volume. It can be all about the market and not much to do with the actual mfg costs.