Grand Seiko SBGA439
Ref. SBGA439 · In production
- Case40 mm
- Thick12.3 mm
- Lug-to-lug46.6 mm
- Water res.100 m
- MovementSpring Drive
- CrystalSapphire
Overview
The Grand Seiko SBGA439 is a sports watch from the Heritage collection. It has a 40 mm stainless steel case, 12.3 mm thick, 46.6 mm from lug to lug. Inside is a spring drive movement (calibre 9R65) with 72 h of power reserve. You also get 100 m water resistance, a sapphire crystal and a bracelet.
Who it suits
- Wrists of roughly 16.0–17.9 cm (6.3–7.0 in), by our Watch Finder sizing guide
- Everyday wear including swimming
Strengths
- Sapphire crystal resists scratches
- Screw-down crown helps keep water out
- 72 h power reserve survives a weekend off the wrist
- Spring Drive: a smooth-gliding seconds hand and high accuracy
- Rated accuracy: ±15 seconds per month (±1 second per day)
Written by Watch.co from the published specs below. These are not owner reviews.
Full specifications
Case
| Case diameter | 40 mm | grand-seiko.com · 23 Oct 2026 |
|---|---|---|
| Thickness | 12.3 mm | grand-seiko.com · 23 Oct 2026 |
| Lug-to-lug | 46.6 mm | grand-seiko.com · 23 Oct 2026 |
| Case material | Stainless steel | grand-seiko.com · 23 Oct 2026 |
| Crystal | Sapphire | grand-seiko.com · 23 Oct 2026 |
| Anti-reflective coating | Anti-reflective coating on inner surface | grand-seiko.com · 23 Oct 2026 |
| Caseback | Screw | grand-seiko.com · 23 Oct 2026 |
| Water resistance | 100 m | grand-seiko.com · 23 Oct 2026 |
| Screw-down crown | Yes | grand-seiko.com · 23 Oct 2026 |
| Magnetic resistance | 4,800 A/m | grand-seiko.com · 23 Oct 2026 |
Dial
| Date | Date | our classification |
|---|---|---|
| Power-reserve indicator | Yes | grand-seiko.com · 23 Oct 2026 |
Movement
| Movement type | Spring Drive | grand-seiko.com · 23 Oct 2026 |
|---|---|---|
| Calibre | 9R65 | grand-seiko.com · 23 Oct 2026 |
| Made in-house | Yes | grand-seiko.com · 23 Oct 2026 |
| Power reserve | 72 h | grand-seiko.com · 23 Oct 2026 |
| Rated accuracy | ±15 seconds per month (±1 second per day) | grand-seiko.com · 23 Oct 2026 |
| Hand-winding | Yes | grand-seiko.com · 23 Oct 2026 |
Strap / Bracelet
| Bracelet / strap | Bracelet | grand-seiko.com · 23 Oct 2026 |
|---|---|---|
| Lug width | 20 mm | grand-seiko.com · 23 Oct 2026 |
Other
| US list price (MSRP) | $5,000 | grand-seiko.com · 23 Oct 2026 |
|---|---|---|
| Production status | In production | grand-seiko.com · 23 Oct 2026 |
| Style (our classification) | Sports | our classification |
Specs are summarised in our own words from the brand's product page. Each row links its source and the date we checked it. Fields we haven't verified are left out rather than guessed.
Variants with the same specs
Same case, movement and bracelet or strap; typically a different dial or finish.
More in Heritage
Similar alternatives
Picked with Watch Finder's style tags and sizing.
Questions about the Grand Seiko SBGA439
How big is the Grand Seiko SBGA439?
The case is 40 mm wide, 12.3 mm thick and 46.6 mm from lug to lug.
What movement does the Grand Seiko SBGA439 use?
It uses the 9R65 calibre, a spring drive movement with 72 h of power reserve.
Can I swim with the Grand Seiko SBGA439?
Yes. It is rated to 100 m.
Does the Grand Seiko SBGA439 have a date?
Yes, it shows the date.
How much is the Grand Seiko SBGA439?
The US list price was $5,000 on grand-seiko.com when we checked on 23 Oct 2026. Prices change, so check before you buy.
Will the Grand Seiko SBGA439 fit my wrist?
By our sizing guide it sits best on wrists of about 16.0–17.9 cm (6.3–7.0 in). Use the fit checker on this page to test your own wrist.
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