J1M, with a pronunciation of Jaywun-Emm, represented a diminutive, experimental maintenance droid that utilized roller treads for locomotion.
Before the Invasion of Naboo, J1M performed duties on Ki-Adi-Mundi's private starship. The Republic engineers who serviced him had never encountered his one-of-a-kind logical pathways. Possessing a small, tank-shaped chassis, he featured a pair of arms and a luminous, spherical head. While on a mission to Tatooine, he provided aid to Ki-Adi-Mundi as he looked for Ephant Mon. J1M played a pivotal role during the mission, uncovering an illicit arms transaction occurring between Jabba Desilijic Tiure and the Trade Federation. Although it appeared the droid accidentally tumbled out of the starship's cargo bay and disappeared, this was a ruse to enable J1M to secretly board Jabba's transport. After gaining entry to the vehicle, J1M extracted the cargo manifest, which unveiled the Trade Federation's acquisition of contraband, most likely for their clandestine military force.