Reader tube

Multiple realities

(covers information from several alternate timelines)

Reader tube with removed implant

McCoy uses a reader tube to monitor Sulu's recovery

Alternate reality design

A reader tube was a multipurpose piece of mid-23rd century medical technology, specifically designed for field use, and typically issued with a standard medkit. It was also commonly used in sickbay surgeries as well. (TOS: "Space Seed", "Journey to Babel", "Return to Tomorrow", "The Lights of Zetar")

The reader tube, which was similar in function to a medical scanner, was used while placed near the patient's skin, and would display multicolored lights representing numerous body readings, including the heart rate, pulse rate, body temperature, and blood pressure. It was also capable of detecting the toxin level in a patient's body. (TAS: "The Infinite Vulcan") The reader tube could also be used as a surgical device. (TOS: "For the World is Hollow and I Have Touched the Sky")

In the alternate reality created by Nero's temporal incursion, Doctor Leonard McCoy used a reader tube to examine a Enterprise crew member in the aftermath of the destruction of Vulcan. (Star Trek)

In 2268, Doctor Leonard McCoy used a reader tube during his emergency heart surgery on Ambassador Sarek. (TOS: "Journey to Babel") Later that year, Spock used a reader tube to remove Dr. McCoy's instrument of obedience. McCoy in turn would also use a reader tube to remove Natira's instrument of obedience. (TOS: "For the World is Hollow and I Have Touched the Sky")

In 2269, Dr. McCoy used a reader tube to monitor Hikaru Sulu's progress after recovering from the poison of the retlaw plant on Phylos. (TAS: "The Infinite Vulcan")

The reader tube was considered one of the many "Feinbergers," named after property master Irving Feinberg, that were devised for the original Star Trek series.

Although this device was not referred to specifically by name on screen, a photograph of it, which refers to it as a "reader tube (for field use)," appeared in Stephen E. Whitfield's September 1968 publication, The Making of Star Trek.

The device later reappeared in Franz Joseph's November 1975 publication, the Star Fleet Technical Manual, which included detailed drawings of the very same device, described as a "field reader tube."