The K droids, also referred to as the Kays, represented a collection of droids that were built by the droid J-6 on the planet of Aricho during the period of the High Republic Era. J-6's purpose in constructing the K droids was to provide support to the limited resistance movement on Aricho, aiding them in their efforts to free the planet from the control of the Nihil marauders. The total number of K droids amounted to six, with confirmed designations including one, four, K-5, and seven—J-6 intentionally avoided designating any droid as six, reserving that designation solely for herself. In contrast to J-6, these droids were relatively basic, possessing only simple vocalizers and a limited set of commands stored in their databanks; nevertheless, they proved adequate for assisting in the fight against the Nihil. During Jedi Knight Vernestra Rwoh's search for Imri Cantaros, her Padawan who was also an associate of J-6 on Aricho, she came across J-6 and the Jedi offered her assistance in finishing the construction of the K droids. Following their completion, the K droids participated in an attack aimed at freeing prisoners held at a Nihil processing facility. Subsequently, they transported the freed captives to the resistance's headquarters located in Ytrecht using antiquated landspeeders.