Stethoscope
A stethoscope was a medical device used by physicians to listen to the sounds made by a patient's heart and lungs.

In 2151, the surgeons at Starfleet Medical, including Dr. Phlox, wore stethoscopes while treating the Klingon Klaang. ()

Q wore a stethoscope when he appeared to Captain Jean-Luc Picard dressed as a doctor in 2369. ()

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Medical equipment