I see that here the movement is listed as a Miyota 8215, but most of the watches that I look up for this watch say that it uses a Seiko 4R35 automatic. I have also seen where the Miyota is listed as "Miyota 8215 (Citizen). I guess I may be getting models confused. Or something........ http://calibercorner.com/miyota-caliber-8215/