What are the case specifications of the Grand Seiko Heritage?

The Grand Seiko Heritage features a 40mm diameter, 12.5mm thick, Steel case with a sapphire crystal crystal.

What is the water resistance of the Grand Seiko Heritage?

The Grand Seiko Heritage has a water resistance rating of 100m (swimming).

What movement does the Grand Seiko Heritage use?

The Grand Seiko Heritage is powered by a Spring Drive, caliber 9R65, 72h power reserve.

Grand Seiko Heritage

Spring DriveSteel

Ref. SBGA387

Collection: HeritageCase size: 40mmMovement: 9R65

The Grand Seiko Heritage, reference SBGA387, is a Spring Drive watch with a 40 mm steel case and is a limited edition of 558 pieces. The case has a thickness of 12.5 mm and a lug-to-lug span of 46.2 mm; water resistance is rated to 100 metres. A dual-curved sapphire crystal has an anti-reflective coating on the inner surface. The watch has a date display, a power reserve indicator, and a see-through case back. A folding clasp with push button release closes the steel bracelet. Calibre 9R65 is Spring Drive with 30 jewels and approximately 72 hours of power reserve.

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Last updated 9 Oct 2026Suggest a correction