Introducing The Seiko Prospex Sumo SPB431 European Limited Edition Watch

Seiko captures the Silfra Fissure's mystique in the latest addition to the Prospex line.


Seiko has once again made waves in the horological world with the release of the Prospex “Sumo” SPB431. Known for its robust construction, reliable performance, and affordable price tag, ‘Sumo’ is a trusted name. This exclusive release, limited to 2,000 pieces and available solely in Europe, draws inspiration from the breathtaking Silfra Fissure in Thingvellir National Park, Iceland and registers itself as a coveted addition to Seiko’s legendary Prospex collection.

The unique barrel-shaped stainless steel case of the SPB431 is robust and measures 45 mm in diameter and with a slim profile of 12.9 mm, echoing the iconic “Sumo” line. Designed with a contemporary silhouette, the watch boasts a screw-down crown strategically positioned at 4 o’clock, which helps to ensure a water resistance of up to 200 meters (20 bar). The two-tone blue and dark green aluminum colorway on the bezel insert pays homage to the Silfra Fissure, and this happens to be the only place on Earth where divers can touch both Eurasian and American continents simultaneously due to the narrowness of the fissure.

The dial as well reflects the deep blue hues of the Silfra Fissure. Along with a box-shaped sapphire crystal featuring anti-reflective treatment, the dial exhibits a captivating contrast that replicates the oceanic straits’ cracks. Lumibrite-filled hands and indexes are guaranteed for optimal readability, even in low-light conditions.

Complementing the dial is a 120-click rotation unidirectional bezel in two-tone blue and dark green aluminum, harmonizing seamlessly with the overall design.

Under the solid caseback lies the reliable Caliber 6R35 movement, operating at a frequency of 3 Hz (21,600 vibrations per hour) and a fairly impressive 70-hour power reserve. This mechanical powerhouse guarantees precision and reliability, reinforcing the watch’s status as a diver’s companion.

Completing the ensemble is a stainless steel bracelet secured by a triple folding clasp with a safety button and push-button release, ideal for underwater adventures. The timepiece also comes with an additional interchangeable blue silicone strap. Priced at EUR 1,100, this limited edition Seiko Prospex “Sumo” SPB431 is available exclusively at European Seiko Boutiques and select authorized retailers.