- "KX-series droids are hardened against intrusion. Getting past their programming is a challenge."
- ―Cassian Jeron Andor
KX-series security droids, also referred to as enforcer droids, were a model of security droid manufactured by Arakyd Industries that was in service to the Galactic Empire during the Galactic Civil War. They were present on both Jedha and the Imperial facility on Scarif. K-2SO and K-4D8 were examples of these droids.
Enforcer droids came equipped with a built-in comm package, recharge port, and a computer interface arm that allowed them to connect with standard communication frequencies for areas they were assigned to. The Imperial crest was imprinted on the side of each shoulder, one of which could be emblazoned in gold if the droid had received an enhanced status. The droids were designed with exaggerated human proportions but with the mobility of a human athlete. They were able to operate a variety or tools and equipment and can carry gear without becoming exhausted.
While the Imperial Senate had prohibited the creation of battle droids, Arakyd was able to use a loophole in the law by marketing the KX-series as "security droids." They were programmed without the standard restriction against harming organic sentient lifeforms.
The KX-series droids were programmed to speak and interact with people, but were not as proficient at it as protocol droids were. They could handle a wide range of tasks, including escorting dignitaries, protecting important people and defending Imperial installations. The droids were also programmed to recognize and defer to Imperial Military officers ranked Lieutenant or higher.