This particular Shure transducer was 60s-70s technology. As it says on that webpage:
"The phone plug connected to the Condor RSM Wind Instrument Synthesizer, made by Innovex. The Condor was based on the electronics of the Hammond orgran and could produce a variety of sounds and effects using the wind instrument as the trigger source. Examples of settings on the Condor: Bass Sax, Fuzz, Cello, Oboe, Tremolo, Vibrato, Bassoon, etc. If the player wanted to use the instrument acoustically, the CA20B would be unthreaded from the adapter and replaced by a brass cap that sealed the side hole in the mouthpiece."
I have got a tenor mouthpiece that has one of these fitted, but it just has the blanking plug, so I haven't been able to use it electronically.
I think that there were/are various other transducers with a similar idea, either fitted to mouthpiece or neck or even the reed.