The n54 medical implant, as seen in Episode 13: Questions.

The n54 medical implant is a device developed by HPlus Nano Teoranta, designed to "track 25 key processes of the human body," including:
  • blood flow
  • heart rate
  • vascular pressure
  • adrenal secretion
  • oxygen intake
  • digestion
  • bone growth
  • circulation
  • excretion
  • heart regulation
  • maintenance of tissue moisture
  • thyroid secretion
  • nutrient absorption
  • salivary secretion
  • carbon dioxide removal
  • ocular transmission
  • cochlear transmission
  • cellular repair
  • immune system response
  • detoxification
  • protein synthesis
  • homeostasis regulation
  • insulin production
  • nervous system response
  • respiration

It is 86 nanometers in diameter, has a protein-based design that is self-forming, and is implanted via saline injection (the starter materials are injected and self-assemble in the body).  The device was designed to monitor many processes of the human body and "act as an early warning system for sufferers of over a dozen diseases."

The device is a predecessor to the later HPlus Implant, and many of its medical functions were incorporated into that device.