Gak-Sixtoo was a nav droid who served the Hutt Bokku, operating aboard Bokku's barge. When Bokku guided the Sith Lord Darth Vader and the Sith assassin Ochi to Zee-Nine City Seven in order to locate the carbonite-frozen smuggler Han Solo, Gak-Sixtoo piloted the vessel, communicating with Ochi as he and Vader disembarked.