Grand Seiko Grand Seiko Spring Drive: The Calibre 9R Movement Explained Spring Drive is neither mechanical nor quartz — it's a third category that combines both approaches. Here's how the 9R calibre actually works.
Grand Seiko Grand Seiko SBGA211 Snowflake: Why It Outperforms Rolex at Half the Price The SBGA211 offers hand-polished Zaratsu case finishing, Spring Drive movement, and textured titanium dial at $6,700 retail. Rolex can't touch it at the price.
