Memory Alpha
Memory Alpha
Multiple realities
(covers information from several alternate timelines)

A Starfleet insignia, inscribed with the wearer's serial number.

Serial numbers, or service numbers, were often used by military organizations as a means of identification.

United States military

Federation Starfleet

22nd century

The serial numbers featured on screen in "The Catwalk" include the initials of the actor; SB for Scott Bakula, JB for Jolene Blalock, and DK for Dominic Keating.

23rd century

Prime reality

Alternate reality

24th century

Terran Empire Starfleet

Michael Burnham mirror badge.jpg

Mirror Burnham's serial number mostly mirrors the prime universe Burnham's Starfleet serial number, except for the order of the letters SHN which remain the same.
The last three characters are illegible on the screen.

See also