This is a simular model, that they use in Rambo Microchip.
The Loudspeaker is a little bit larger, and even fits the ear.
RFID is CMOS Compatible, and a frequency connect them to "CMOS MEMS Loudspeaker" and "CMOS MEMS Microphone", wireless. Also can they use without RFID directly with a transceivers or Satellite Modem together with RFID.
Here is pictures with Some of this wireless CMOS MEMS Laoudspeaker and CMOS MEMS Microphones (front and behind side) and my finger.
All the best
Jan Azim Svanberg