In a parallel universe, a registry number was used to identify the starships of the Starfleet of the United Federation of Planets.
In the 23rd century, the Constitution-class USS Enterprise's registry number was NCC-1701. Among its shuttlecraft was the Galileo, registry number NCC-1701/7. By the 24th century, it had been succeeded by a new USS Enterprise, registry number NCC-1701-D.
The USS Kessler, a contemporary of the succeeding Enterprise, was identified by the registry number NCC-65527. (COMIC: Assimilation²)