Fulstar plates were magnetized metal components critical to hyperdrive use. Jumping to hyperspace without one equipped would result in destruction. Distinguished by shape and color, each starship class required a particular style of plate.
Fulstar plates were magnetized metal plates available in various shapes and colors. They were small enough to be held by a Human in one hand, and the face of each plate was marked by a pattern of dots and lines. Part of the hyperdrive system, jumping to hyperspace without one would cause a vessel's destruction. Each starship class required a specific style—plates with round sides only worked in T-65 X-wing starfighters, and the YT-1300 light freighter Millennium Falcon required a square, red plate.
At some point during the Galactic Civil War, the protocol droid C-3PO and his astromech counterpart R2-D2 attempted to assist the Rebel Han Solo and his Wookiee first mate Chewbacca with repairs to their tramp freighter, the Millennium Falcon, by locating a red, square fulstar plate that Captain Solo needed. A supply room aboard the Falcon held square plates in multiple colors, but C-3PO's photoreceptors were damaged when he knocked over some supplies, and he could not identify the correct color plate. After a process of trial and error, and help from the Falcons central computer, he brought the correct plate to Solo. The plate was then installed and the hyperdrive fixed.
Rebel quartermasters kept round fulstar plates on hand, and the scavenger Zilnor was a supplier of triangular and pentagonal fulstar plates.
The Falcon evades TIE fighters amongst a cloud of plates.
Fulstar plates were introduced in 1984's Star Wars Adventures in Colors and Shapes, an educational Read-Along Adventures book-and-record for young readers published by Buena Vista Records. The cover of the book depicts C-3PO and R2-D2 alone in the cockpit of the Millennium Falcon being pursued by TIE fighters in the midst of a cloud of random shapes, most likely the fulstar plates around which the story revolves. This event is not depicted in the narrative.
Fulstar plates were going to be featured in Ryder Windham's The Big Switch, the third book in the young-readers series Star Wars: Adventures in Hyperspace. The book, however, went unpublished after it was announced that the Expanded Universe had been rebranded as Star Wars Legends, and that new content within past Legends series would not be published.