XXI's bracelet

These bracelets, created by the brothers McNamara, were used to enslave demons, of whom Angel, and to force them to fight to death on a boxing ring in XXI. Whoever wearing the bracelet, wanted to escape, risked to finish split (a line being painted on the ground served to remin) it).Wesley and Cordelia finds a solution to open bracelets. Being electric and not magic, it is a hair of Cordelia's horse (before his father went bankrupt) who serves as key.