Designed with a stainless steel case and bracelet, this 44.2mm Grand Seiko Caliber 9R65 diver watch, features the signature Grand Seiko clear ridges on the facets of the case and luminous hands and markers on a matte black dial. Spring Drive, a unique Seiko movement that requires neither a battery nor an electric motor, makes it a completely self-contained system. Its power is derived from a mainspring, just like a mechanical watch, and its accuracy is controlled by the precise signal of a quartz oscillator. These watches are all accurate to ±10 seconds per month, a level that is higher than any other existing spring-wound watch in the world. Featuring a one-way rotating bezel, Spring Drive movement allows for self and automatic winding capabilities and features 30 jewels, with accuracy /- 1 second per day with over 72 hours power reserve. 200M Water Resistant