A Periaktoi is an ancient device, often thought to be of Greek origin, that is still used for stage scene changes. It is usually a triangular unit with (3) equal sides. Each side can have a different scene painted on it. When using more then one* Periaktoi in a row, it can look like a solid wall. When all the units are rotated to the second or third side, it reveals another scene. One of the most well known shows to currently use Periaktoi is "A Chorus Line."