They were two mechanisms which were often confused by the ancient writers. The “ekkyklima” was a low-wheeled vehicle for transporting the dead, objects, etc. on stage. The “exostra” was a low rotating platform (around an axle) of half-circular form for the rapid appearance and change of the interior scene precursor of modern rotating stages on a wagon.

SOURCES: Pollax Julius, Onomastikon, Isychios the Lexicographer, Lexicon.