Catherine-B320

"This is Sierra-320, prepped for combat insertion"

- Sierra-320.

Kat-320 is a SPARTAN-III Commando of the UNSC Naval Special Warfare Command. She fought with Noble Team during the Battle of Reach in 2552. She is the team's second-in-command, and is described as being fiercely loyal to Carter-259 and the team. This devotion also cost her right arm, which has been replaced by a robotic implant.