I have the Elegiant model, that looks like a rebranded model of the other proposition by Levy_Wilson (and alittle cheaper ^^ ), works fine. Juste replaced the jack cable with a shorter one to keep all in my pocket :) I'm using it with a Bose QC35 :) Car has a Kenwood MD unit <3

Using a close model by Elegiant, I'm happy with it (and my QC35 :) )

This other user has a much more compact model, could be worth to look for it
https://www.reddit.com/r/minidisc/comments/lzlp6a/mzrh1_crystal_method_bluetooth_transciever/