Seiko SRPD55
Ref. SRPD55 · In production
- Case42.5 mm
- Thick13.4 mm
- Water res.100 m
- MovementAutomatic
- CrystalHardlex (Seiko mineral)
Overview
The Seiko SRPD55 is a diver watch from the Seiko 5 Sports collection. It has a 42.5 mm stainless steel case, 13.4 mm thick. Inside is a automatic movement (calibre 4R36) with 41 h of power reserve. You also get 100 m water resistance and a hardlex (seiko mineral) crystal.
Who it suits
- Wrists of roughly 17.0–18.9 cm (6.7–7.5 in), by our Watch Finder sizing guide
- Everyday wear including swimming
Trade-offs
- Hardlex (Seiko mineral) crystal scratches more easily than sapphire
- 41 h power reserve: it stops after about a day and a half off the wrist
Written by Watch.co from the published specs below. These are not owner reviews.
Full specifications
Case
| Case diameter | 42.5 mm | seikowatches.com · 23 Oct 2026 |
|---|---|---|
| Thickness | 13.4 mm | seikowatches.com · 23 Oct 2026 |
| Case material | Stainless steel | seikowatches.com · 23 Oct 2026 |
| Crystal | Hardlex (Seiko mineral) | seikowatches.com · 23 Oct 2026 |
| Water resistance | 100 m | seikowatches.com · 23 Oct 2026 |
Movement
| Movement type | Automatic | seikowatches.com · 23 Oct 2026 |
|---|---|---|
| Calibre | 4R36 | seikowatches.com · 23 Oct 2026 |
| Power reserve | 41 h | seikowatches.com · 23 Oct 2026 |
Strap / Bracelet
| Lug width | 22 mm | seikowatches.com · 23 Oct 2026 |
|---|
Other
| US list price (MSRP) | $350 | seikowatches.com · 23 Oct 2026 |
|---|---|---|
| Production status | In production | seikowatches.com · 23 Oct 2026 |
| Style (our classification) | Diver | seikowatches.com · 23 Oct 2026 |
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.
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Picked with Watch Finder's style tags and sizing.
Questions about the Seiko SRPD55
How big is the Seiko SRPD55?
The case is 42.5 mm wide, 13.4 mm thick.
What movement does the Seiko SRPD55 use?
It uses the 4R36 calibre, a automatic movement with 41 h of power reserve.
Can I swim with the Seiko SRPD55?
Yes. It is rated to 100 m.
How much is the Seiko SRPD55?
The US list price was $350 on seikowatches.com when we checked on 23 Oct 2026. Prices change, so check before you buy.
Will the Seiko SRPD55 fit my wrist?
By our sizing guide it sits best on wrists of about 17.0–18.9 cm (6.7–7.5 in). Use the fit checker on this page to test your own wrist.
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