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"Every clone has an identifying code on their wrist. Your military records will be in the database. Scan him, Artoo."
Colonel Meebur Gascon, to CC-5576-39[src]

An identifying code was used by the Galactic Republic, in order to identify and distinguish clone troopers. The code was inserted into a clones' left wrist and would link droids, such as astromechs, to the trooper's file in the Grand Army of the Republic military database.