Prospex Sumo Diver

A 45mm Zaratsu-polished case around the 6R35 automatic — 70 hours of reserve, unidirectional bezel, and a sunburst dial that shifts from navy to near-black as the light moves. The reference that made desk-diving respectable.

Movement: Automatic

Case Material: 316L Stainless Steel

• Model, movement, case and dial details listed for comparison
• Product code WCH-DXTJDJ59 listed for order confirmation
• Included warranty coverage is shown in the specifications when available
• Automatic movement with listed case specifications
• Brand listed as Seiko

Winding & Setting

Hand-wind an automatic 20–30 turns before first wear. Never adjust the date between 9pm and 3am — the date wheel is engaged and forcing it strips the mechanism. Always screw the crown back down before contact with water.

Water Resistance

The rating on the case back assumes fresh gaskets. Rinse with fresh water after sea or chlorinated water, and have gaskets pressure-tested every two years regardless of how the watch is worn.

Service & Storage

A mechanical movement typically needs periodic servicing. Store it away from speakers, laptops and magnetic clasps, and keep the box and any included documents.