The details

Everything worth knowing.

Verified catalogue information, practical sizing guidance and the details that help you decide.

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 sport(ing 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.

• In 2025, Grand Seiko unveiled the Spring Drive Calibre 9RB2, a groundbreaking movement that received the then-new U.F.A.
• 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.
• Dive Watches selected from Grand Seiko's current catalogue

Product type

Dive Watches

Colours

1

Sizes listed

Not sized

Reference

FH-P-2AEC6444FDD1