The Seiko 6530-5590 is an electrical Swiss wrist-watch movement introduced from 1960 to 1961. It is equipped with an electromechanically controlled balance motor and features a sweep second function. The early samples of this movement lack an excenter regulator, while the standard mounting frame measures Dm=Do=30.2mm. It is an electronic movement that offers central hours, central minutes, and central sweeping seconds.