A containment shield functioned as a device capable of preventing passage into a designated space, using a field to achieve complete isolation. On starships, this device could effectively segregate one room from all other areas of the vessel. Around 379 BBY, a containment field was implemented on the Gaze Electric, a ship owned by Marda Ro. Ro, the ship's proprietor, utilized it to confine a beast identified as the Great Leveler within the ship's medical observation room. Approximately in that year, she turned off the field, allowing the Leveler to feed on a Jedi. Subsequently, Ro recorded a message for her descendants, making mention of the containment shield. By 252 BBY, her great-great-grandson, Marchion Ro, had heard the message referencing the containment shield.
Around 379 BBY, the Gaze Electric was outfitted with a containment field. The ship belonged to Marda Ro, the Evereni who founded a pirate group that would later evolve into the Nihil. She employed the containment field to hold captive the Great Leveler, a monster that preyed upon the Living Force, within the Gaze Electric's medical observation room. In that same year, Ro attacked a Jedi and brought him onto the Gaze. Her subordinate, Rox, positioned the Jedi near the containment shield, behind which the Leveler was kept. Ro then deactivated the shield, allowing the Leveler to feed on the Jedi, before guiding it back into the room after it had transformed the Jedi's body into a [stone]-like husk. Later on, Ro mentioned the shield in a message that she recorded for her descendants. By 252 BBY, during his younger years, Ro's great-great-grandson, Marchion Ro, had listened to her journal, including the section where the containment shield was mentioned.
A containment shield made an appearance in the current Star Wars canon within a flashback featured in the short story "A Closed Fist Has No Claws," penned by Tessa Gratton. It was published in the 2023 young-adult anthology The High Republic: Tales of Light and Life as part of the larger Star Wars: The High Republic multimedia endeavor. This technology originated in the Star Wars Legends continuity, debuting in the short story "Of Possible Futures: The Tale of Zuckuss and 4-LOM," authored by M. Shayne Bell and released in the 1996 short story anthology Tales of the Bounty Hunters.