Memory Beta, non-canon Star Trek Wiki
A friendly reminder regarding spoilers! As always, the expanded Trek universe is in a period of major upheaval with the continuations of Strange New Worlds and Prodigy, the advent of new eras in gaming with the Star Trek Adventures RPG and Star Trek Online, as well as other eventful releases such as Section 31, the ongoing IDW Star Trek comic and spin-off Star Trek: Defiant. Therefore, please be courteous to other users who may not be aware of current developments by using the {{spoiler}}, {{spoilers}} OR {{majorspoiler}} tags when adding new information from sources less than six months old (even if it is minor info). Also, please do not include details in the summary bar when editing pages and do not anticipate making additions relating to sources not yet in release. THANK YOU
READ MORE
A tracer device or tracking device was a technology used for tracking the location of a person or object.
In the year 2266, Spock hid a tracer device in the shuttlecraft stolen by a Klingon duplicate of James T. Kirk and used it to follow him to the planet Beta II, where the real Kirk was being held prisoner. (TOS comic: "The Enterprise Mutiny")