NEW

SLGB025 SLGB025G

Evolution 9 Collection

$17,700

Pre-Order

Despatch will take place June/July 2026 with full tracking

Contact a Boutique

Book an Appointment

Features

The “Ushio 300,” a Spring Drive diver’s watch with phenomenal accuracy and a stunning green dial.

In 2025, Grand Seiko unveiled the Spring Drive Calibre 9RB2, a groundbreaking movement that received the then-new U.F.A. designation, standing for “Ultra Fine Accuracy.” Boasting an annual accuracy rate of ±20 seconds, Calibre 9RB2 earned the distinction of being the most accurate wristwatch movement powered by a mainspring.* This model is powered by Calibre 9RB1, featuring an improved construction that makes it ideal for sporting conditions while sharing the same attributes as the Calibre 9RB2.

The term "ushio", which means “tide” in Japanese, evokes the waters that surround the Japanese archipelago. The green dial draws from the tranquil beauty of shallow coastal waters near the shore.

* As of April 2026, based on Grand Seiko’s research.

Any purchase through our Grand SEIKO Online Store has a 5 Year limited guarantee

Specifications

Exterior

Case Material:	High Intensity Titanium
Glass Material:	Sapphire Glass with Anti-Reflective Coating on the Inside
Case size:	Diameter: 40.8mm Thickness: 12.9 mm Length: 48.5mm
Case Colour:	Silver
Band/Bracelet:	Bracelet - High Intensity Titanium
Band Colour:	Silver
Band Reference:	A0EY123T0
Dial Colour:	Green Textured
Hand Indicators:	Hour, Minute, Seconds
Dial Markers:	Batons
Crown:	Screw Down
Rotating Bezel:	One Way

Movement

Calibre no.:	9RB1 Instructions
Movement Type:	Spring Drive - Powered By The Movement of the Wearer
Accuracy:	±20 seconds per year
Power Reserve:	72 Hours Power Reserve
Display:	Analogue

Functions

Water Resistance:	Divers 300 Metres
Other details / Features:	Hand Winding Power Reserve Indicator

The three movements at the heart of Grand Seiko

9SMechanical

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.

9RSpring Drive

Spring Drive is a unique movement that delivers one-second-a-day precision, using just the power of a mainspring.

9F Quartz

The ultimate quartz movement. Calibre 9F incorporates several unique technologies that raise the performance of quartz to the high standards of Grand Seiko.

Collections

Masterpiece Collection

Evolution 9 Collection

Heritage Collection

Sport Collection

Elegance Collection

SLGB025 SLGB025G

Features

The “Ushio 300,” a Spring Drive diver’s watch with phenomenal accuracy and a stunning green dial.

Specifications

The three movements at the heart of Grand Seiko

Shopping Cart