Stun cuffs, also known as cuffs or simply binders, were devices made of durasteel used to restrict the movement of a captive's limbs. The thin but unbreakable cuffs were commonly used to bind a prisoner's hands, but could also be used to bind both feet, one arm and one leg, or one limb to a stationary object to further immobilize a captive.
These devices were used on criminals to hold them in custody so they could not escape. The cuffs would stun the prisoner if a button was pressed by the guard or, in some cases, if the prisoner resisted too much. However, Jedi and other Force-trained beings proved far more difficult to restrain than average beings using stun cuffs.
The Geonosians used binders on their prisoners in their gladiatorial arenas on Geonosis. These binders had pulse lock points that welded the clasps tight. They also featured an electronic release mechanism. Obi-Wan Kenobi, Anakin Skywalker, and Padmé Amidala were fitted with such binders for their scheduled execution in the Petranaki arena, but were able to defeat their captors and executioners. The Confederacy of Independent Systems also made use of binders, replete with duranium cinch-locks.
Binders were used aboard the first Death Star to restrain dangerous prisoners. Han Solo fitted Chewbacca with a pair of binders when he and Luke Skywalker posed as stormtroopers in their attempt to rescue Leia Organa. Skywalker was originally going to outfit Chewbacca with the binders, but he had Solo do it instead after the Wookiee snarled at him. They unlocked the binders before entering the detention block, allowing the Wookiee to "break free" and aid his companions in the firefight that followed.