Grand Seiko Evolution 9 Collection Ushio 300 SLGB023
Grand Seiko Evolution 9 Collection Spring Drive U.F.A. Ushio 300 Diver SLGB023
In 2025, Grand Seiko unveiled the Spring Drive Caliber 9RB2, a groundbreaking movement that received the then-new U.F.A. designation, standing for âUltra Fine Accuracy.â Boasting an annual accuracy rate of ±20 seconds, Caliber 9RB2 earned the distinction of being the most accurate wristwatch movement powered by a mainspring.* This model is powered by Caliber 9RB1, featuring an improved construction that makes it ideal for sporting conditions while sharing the same attributes as the Caliber 9RB2.
The term ushio, which means âtideâ in Japanese, evokes the waters that surround the Japanese archipelago. This creationâs blue dial reflects the vast expanse of the sea through a gradient that captures light streaming into the deep ocean.
Specifications
| Exterior: | High-intensity titanium |
|---|---|
| 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 40.8mm Lug-to-lug 48.5mm Thickness 12.9mm |
| Band width: | 21mm |
| Clasp type: | Locking extension clasp with micro-adjustment |
Movement
| Caliber no.: | 9RB1 Instructions |
|---|---|
| Movement Type: | Spring Drive |
| Power reserve: | Approx. 72 hours(3 days) |
| Accuracy: | ±20 seconds per year (±3 seconds per month) |
Functions
| Water resistance: | 300m / 1000ft diver's |
|---|---|
| Magnetic resistance: | 4,800 A/m |
| Other details / Features: |
|
Grand Seiko Evolution 9 Collection Ushio 300 SLGB023
Grand Seiko Evolution 9 Collection Spring Drive U.F.A. Ushio 300 Diver SLGB023
In 2025, Grand Seiko unveiled the Spring Drive Caliber 9RB2, a groundbreaking movement that received the then-new U.F.A. designation, standing for âUltra Fine Accuracy.â Boasting an annual accuracy rate of ±20 seconds, Caliber 9RB2 earned the distinction of being the most accurate wristwatch movement powered by a mainspring.* This model is powered by Caliber 9RB1, featuring an improved construction that makes it ideal for sporting conditions while sharing the same attributes as the Caliber 9RB2.
The term ushio, which means âtideâ in Japanese, evokes the waters that surround the Japanese archipelago. This creationâs blue dial reflects the vast expanse of the sea through a gradient that captures light streaming into the deep ocean.
Specifications
| Exterior: | High-intensity titanium |
|---|---|
| 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 40.8mm Lug-to-lug 48.5mm Thickness 12.9mm |
| Band width: | 21mm |
| Clasp type: | Locking extension clasp with micro-adjustment |
Movement
| Caliber no.: | 9RB1 Instructions |
|---|---|
| Movement Type: | Spring Drive |
| Power reserve: | Approx. 72 hours(3 days) |
| Accuracy: | ±20 seconds per year (±3 seconds per month) |
Functions
| Water resistance: | 300m / 1000ft diver's |
|---|---|
| Magnetic resistance: | 4,800 A/m |
| Other details / Features: |
|
Product Information
Product Information
Shipping & Returns
Shipping & Returns
Description
Grand Seiko Evolution 9 Collection Spring Drive U.F.A. Ushio 300 Diver SLGB023
In 2025, Grand Seiko unveiled the Spring Drive Caliber 9RB2, a groundbreaking movement that received the then-new U.F.A. designation, standing for âUltra Fine Accuracy.â Boasting an annual accuracy rate of ±20 seconds, Caliber 9RB2 earned the distinction of being the most accurate wristwatch movement powered by a mainspring.* This model is powered by Caliber 9RB1, featuring an improved construction that makes it ideal for sporting conditions while sharing the same attributes as the Caliber 9RB2.
The term ushio, which means âtideâ in Japanese, evokes the waters that surround the Japanese archipelago. This creationâs blue dial reflects the vast expanse of the sea through a gradient that captures light streaming into the deep ocean.
Specifications
| Exterior: | High-intensity titanium |
|---|---|
| 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 40.8mm Lug-to-lug 48.5mm Thickness 12.9mm |
| Band width: | 21mm |
| Clasp type: | Locking extension clasp with micro-adjustment |
Movement
| Caliber no.: | 9RB1 Instructions |
|---|---|
| Movement Type: | Spring Drive |
| Power reserve: | Approx. 72 hours(3 days) |
| Accuracy: | ±20 seconds per year (±3 seconds per month) |
Functions
| Water resistance: | 300m / 1000ft diver's |
|---|---|
| Magnetic resistance: | 4,800 A/m |
| Other details / Features: |
|
