4B-X, also known as Forbee-X, was a science research droid of feminine programming that was associated with the Alliance to Restore the Republic. During the year 0 ABY, she accompanied Governor Trux Zissu, Stuart Zissu, R2-D2, and C-3PO on a mission originating from Yavin 4. Their destination was the planet Delantine, and they traveled aboard the vessel named Timespan. After an Imperial warship attacked the Timespan and captured Governor Zissu, the remaining members of the crew made their escape in an escape pod. This pod ultimately crash-landed on the planet Da'nor, leaving them stranded.
Forbee-X, or 4B-X, navigated using wheels and featured a sizable screen that formed the majority of her egg-shaped head. This screen had the ability to shift its colors or display schematics. While she typically moved on her wheels, she had the ability to retract them and instead utilize feet equipped with elongated steel toes for traversing rough terrain. These feet also possessed spikes, which could be deployed to enhance her grip. The screen on her head tended to flicker when she was using her sensors or when she was speaking. In addition, 4B-X possessed metal webbing that could extend between her digits, functioning as paddles. Her outer shell was constructed from a material designed to absorb impacts. She was known for her high level of enthusiasm and her fondness for performing calculations.
4B-X made her debut appearance in the Star Wars Legends young adult novel, Star Wars Science Adventures: Emergency in Escape Pod Four. This novel was authored by Jude Watson and K.D. Burkett, with illustrations provided by Frank Boyd Forney. It was released to the public in the year 1999.