With its screw-down crown, distinctive hands generously coated with Lumibrite, one-way rotating bezel and water resistant to a depth of 200 meters, this watch provides all the security and legibility that the diver requires. It also offers the precision and durability of Grand Seiko's divers' high-beat movement, Caliber 9S85.
Each hand is different, to ensure that the time can be read easily and without error and the triangular marker at twelve o’clock ensures that, even at depth, no mistake is made.
Every component is built to last, but all divers know that their watch needs regular maintenance, just like every other device on which his or her life may depend. This is why the case, stem pipe and crown are designed for secure servicing and even the bezel has a four-part design that makes for easy disassembly and re-assembly at the Grand Seiko Service Centers.  

Exterior

Case Material: High-intensity titanium

Glass Material: Sapphire crystal

Glass Coating: Anti-reflective coating on inner surface

LumiBrite: LumiBrite on hands, indexes and bezel

Case size: Diameter 43.8mm × Thickness 14.7mm

The perimeter of Band: 190mm

Clasp type: Three-fold clasp with secure lock & push button release, solid & slide adjuster

Movement

Caliber no.: 9S85 Instructions

Movement Type: Automatic with manual winding

Power reserve: Approx. 55 hours

Accuracy: 5 to -3 seconds per day (mean daily rate)

Functions

Water resistance: 200m / 660ft diver's

Magnetic resistance: Equipped

Weight: 142.0 g

Other details / Features:  

・37 jewels

・Case back with lion emblem

・Date display

・Screw case back

・Screw-down crown

・Stop seconds hand function

・Three-fold clasp with secure lock

・Unidirectional rotating bezel