The Sith Har were an order of mysterious assassins, about who little was known.
History and specifics[]
They manufactured the Sith Har Blaster, a highly deadly exotic firearm, exported to other species such as the Klingon Empire. It was unknown where they were based, but Drema IV was suspected, or else somewhere else in the Drema system. (TNG video game: Klingon Honor Guard)