Grand Seiko Evolution 9 Collection
Diver’s watch with 5-day Spring Drive movement
Featuring the Evolution 9 Style, 200 meters of water resistance, and a blue variation on the “ushio” dial initially seen in 2022 in black, the new Reference SLGA023 is the latest diver’s watch from Grand Seiko. Below its distinctive, patterned dial is the Spring Drive Caliber 9RA5, a next-generation movement with automatic winding, ±10 seconds per month accuracy, and a power reserve of 120, or about five days, when fully wound.
The Evolution 9 Style is a set of original design techniques intended to further pursue usability and beauty in wristwatches and is a development upon the Grand Seiko Style. This sports watch combines these design elements with compliance with ISO standards to satisfy the requirements for a diver’s watch, with increased readability, operability, and robustness.
The coastal waters of Japan are influenced by the flow of the Kuroshio Current, one of the world’s major ocean currents, as well as by the nutrient-rich waters of the Oyashio Current, creating one of the world’s most diverse ocean regions. The dynamic undulation of the waves of these ocean currents is expressed in the powerful dial pattern of this watch, which also uses a unidirectionally rotating bezel with an insert made of ceramic. However, unlike last year’s Spring Drive diver’s watch, which was black, this year the dial and bezel are in Grand Seiko blue.
|Case back:||Screw case back|
|Glass Material:||Sapphire crystal|
|Glass Coating:||Anti-reflective coating on inner surface|
|LumiBrite:||LumiBrite on hands, index(es) and bezel|
|Case size:||Diameter 43.8mm Lug-to-lug 51.5mm Thickness 13.8mm|
|Clasp type:||Three-fold clasp with secure lock & push button release, solid & slide adjuster|
|The perimeter of Band:||185mm|
|Magnetic resistance:||4,800 A/m|
|Other details / Features:||
The essence of Grand Seiko is infused with Japanese beauty
The Evolution 9 Collection is based on the Evolution 9 Style, a new design methodology born from the pursuit of the ideal wristwatch. Through these efforts, Grand Seiko is forging a new path.
Greater readability for the hands and index to meet the needs of a diver’s watch
In 2020, Grand Seiko introduced a new design philosophy called the Evolution 9 Style. It was based, of course, on the Grand Seiko Style, which has always defined the design of all Grand Seiko watches and continues to do so. The Evolution 9 Style preserves the fundamentals of the Grand Seiko Style but adapts them for a new generation by setting new standards of legibility, comfort, and beauty.
This timepiece was developed to meet the needs of divers. To allow the wearer to quickly read the watch, the contrast between the dial and the hands has been emphasized. LumiBrite is used on the hour and minute hands as well as the indexes to give them greater presence. Through these techniques, Grand Seiko’s newest diver’s watch achieves superior readability.
Spring Drive 5 Days Caliber 9RA5
Spring Drive is a unique watch technology. It generates energy like every other traditional mechanical watch but combines this with an electronic regulator to deliver a level of precision that no mechanical watch can match. The development of Spring Drive was possible because Grand Seiko is one of the very few manufacturers with mastery of both electronic and mechanical watchmaking.
In addition to achieving a high accuracy of ±10 seconds/month, this movement is 0.8mm thinner than the previous Caliber 9R65 by adopting the “Offset Magic Lever.” The movement is equipped with a power reserve indicator located on the dial side for safety during diving.
The three movements at the heart of Grand Seiko
One of the world's foremost mechanical movements, the culmination of high-precision micro-engineering and the attention to detail of Seiko's expert watchmakers.
Spring Drive is a unique movement that delivers one-second-a-day precision, using just the power of a mainspring.