Uploaded April 2022 | Updated September 2026, 13 hours ago

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The most complicated watch created by Grand Seiko incorporates a constant-force mechanism and a tourbillon as one unit on a single axis. Its Caliber 9ST1 delivers a level of stable accuracy unprecedented for Grand Seiko. Full details at timeandwatches.com/2022/04/grand-seiko-kodo-constant-force.html