Fulstar plates, composed of magnetized metal, played an essential role in the operation of hyperdrives. Catastrophic failure would occur if one attempted a jump to hyperspace without this component. Plates were made distinct by their shapes and colors, with each starship class requiring a plate of a specific configuration.
These magnetized metal plates, known as Fulstar plates, came in a variety of shapes and colors. A Human could easily hold one in their hand. The surface of each plate was etched with a pattern of lines and dots. Integral to the hyperdrive system, failure to have one installed when jumping to hyperspace would result in the destruction of the vessel. Different starship classes needed unique plates; for instance, the T-65 X-wing starfighter required round plates, while the YT-1300 light freighter Millennium Falcon demanded a red, square plate.
During the Galactic Civil War, the protocol droid C-3PO and his astromech counterpart R2-D2 tried to assist Han Solo, a Rebel pilot, and his Wookiee first mate Chewbacca in repairing their tramp freighter, the Millennium Falcon. Their mission was to find a red, square fulstar plate that Captain Solo needed. The Falcon's supply room contained square plates of various colors. However, C-3PO's photoreceptors were damaged when he accidentally knocked over some supplies, rendering him unable to identify the correct color. Through a process of elimination, and with assistance from the Falcon's central computer, he eventually located the correct plate and gave it to Solo. The hyperdrive was then repaired after the plate's installation.
Quartermasters serving the Rebel Alliance kept round fulstar plates in stock, and the scavenger Zilnor supplied triangular and pentagonal versions.
Fulstar plates made their debut in the 1984 educational Read-Along Adventures book-and-record for young readers, Star Wars Adventures in Colors and Shapes, published by Buena Vista Records. The book's cover depicts C-3PO and R2-D2 alone in the cockpit of the Millennium Falcon while being pursued by TIE fighters amid a cloud of random shapes, which are most likely the fulstar plates that are central to the story. This specific event is not portrayed in the book's narrative.
Plans existed to include Fulstar plates in Ryder Windham's The Big Switch, the third installment in the Star Wars: Adventures in Hyperspace series for young readers. However, the book was never released after the Expanded Universe was rebranded as Star Wars Legends, and the decision was made to halt the publication of new content within existing Legends series.