A fitting tribute to the legendary Seiko "Tuna"

In 1986, Seiko launched a diver's watch that set a new standard. It combined Seiko's legendary 1975 design with a 1,000 meter water resistance for saturation diving with a quartz movement that delivered an accuracy that no mechanical diver's watch could match. At the time, and still today, it was recognized as one of Seiko's most important diver's watches. Today, 35 years later, this classic Seiko Diver's watch is re-born as reference S23635 with new design features and upgraded professional diver's watch specifications.

This new reference is purpose-built to live up to the promise of the Prospex name. The dial color has a gradation from blue to black to dramatize the way that light gradually fades as one dives deeper into the dark, mysterious world of the ocean. It incorporates the unique one-piece titanium case with its outer protector structure that makes its shock resistance so exceptional. The crown is marked with a vivid yellow 'Lock' sign and an arrow to indicate the rotating direction. The winding stem is also in yellow so that the wearer can immediately notice if the crown is unlocked. Following ISO standards for saturation diving at depths of up to 1,000 meters, this high-intensity watch is powered by a quartz caliber 7C46 movement, engineered specifically for diver's watches with increased torque to move the heavy hands, as well as enhanced battery life. Including a day/date window, LumiBrite hands and markers, sapphire crystal and a stainless steel bezel with super-hard coating, this landmark timepiece comes packaged in a special collectors' box.

Specifications

• 49.4mm x 17.2mm
• Monocoque titanium case with protective ceramic shroud
• Sapphire crystal – 60-minute unidirectional bezel
• 1000m WR
• Blue gradient dial with Lumebrite
• Calibre 7C46 quartz with day/date complication (Japan Domestic Model with 'bilingual' day aperture in Kanji & English)
• Battery life: 5 years
• Magnetic-resistance 40,000 A/m
• Blue silicone strap
• Japan Domestic Market (JDM) limited edition, 1,200 pieces