This professional diver's model features the Caliber 9S85, outstanding precision of +5 to -3 seconds a day, that can withstand pressures encountered in saturation diving, down to a depth of 600 meters.The groove on the rotating bezel ensures a firm grip even with thick diving gloves. Luminous markers at every ten seconds ensure the legibility that brings safety to the deep sea diver. 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 and crown are designed for secure servicing and even the bezel has a four-part design that makes for easy disassembly and re-assembly.The dial is made of pure iron in order to protect the movement from the harmful effects of magnetism. It delivers safe and secure use during diving, in addition, every-day usability is also assured. The watch also features distinctive clean edges appearing in a complex polyhedron and a distortion-free mirror surface created by experts using Zaratsu polishing. The dial of the limited edition is made in the exclusive color that signifies craftsmanship and tradition in Japan and is the signature color of Grand Seiko. The watch also comes with an additional extra-strength silicone strap, in the deep Grand Seiko blue to match the dial, so that you can change the appearance of the watch at will.