Najus

Najus was a Sith artisan who at one point pursued a vendetta against the Jedi Order. To aid with his efforts, Najus crafted the powerful and legendary dark side artifacts known as the Bracers of Najus. To discourage anyone from utilizing the bracers against the Sith, Najus designed them so that they provided no beneficial effect to their wielder when used against an opponent who drew upon the dark side of the Force—and in fact even aided such an adversary. At some point, the Bracers of Najus were transported by a group of Sith aboard a starship that eventually crashed on the planet Leritor, where the vessel remained buried for centuries.

Text and facts from the “Najus” article on Wookieepedia, licensed under CC BY-SA 3.0. Modified for this site.