From Holden’s Watch Desk research
Seiko Samurai SRPL51
The Seiko Samurai SRPL51 (SRPL51K1) is a dive watch from Seiko: a 41.7 mm stainless steel case, 12.3 mm thick and 49.5 mm lug to lug, with an automatic 4R35 movement and 200 m water resistance.
Going by its 49.5 mm lug to lug, it should sit within the flat top of a wrist of about 6.7 inches (17.1 cm) or larger.
Research found it at $595 list in the US (checked August 2026), about $542–575 on the street (August 2026) and about $407–662 used (August 2026).
Specifications
From the research, with the sources for each group of facts. Unknown means no source confirmed it.
| The watch [1][2][3][4] | |
|---|---|
| Brand | Seiko |
| Reference | SRPL51K1 |
| Category | Diver |
| Production | Current (introduced 2025) |
| Case and size [1][2] | |
| Case diameter | 41.7 mm |
| Lug to lug | 49.5 mm |
| Thickness | 12.3 mm |
| Lug width | 20 mm |
| Case material | Stainless steel |
| Crystal | Hardlex |
| Water resistance | 200 m / 660 ft diver's specification |
| Weight | 170 g |
| Movement [1][2] | |
| Movement | 4R35, automatic |
| Power reserve | Approx. 41 hours (official; Teddy states 42 h) |
| Accuracy | Unknown |
| Bracelet [1][2] | |
| Bracelet or strap | Three-link stainless steel bracelet |
| Clasp | Three-fold clasp with secure lock, push-button release, wetsuit/diver extension |
| Price and warranty (US) [1][2][3] | |
| List price (US) | $595 (official US page, 2026-08) |
| Street price (US) | $542-$575 new on Chrono24 (2026-08) (August 2026) |
| Used price (US) | ~$407-$662 across Chrono24 listings depending on condition/location (August 2026) |
| Warranty | Unknown |
Will it fit?
A watch wears comfortably when its lugs stay on the flat top of the wrist. Here is the 49.5 mm lug to lug against the flat top estimated for common wrist sizes.
| Wrist | Flat top | Fit |
|---|---|---|
| 6 in 15.2 cm | 47 mm | Likely overhangs |
| 6.5 in 16.5 cm | 51 mm | At the edge |
| 7 in 17.8 cm | 55 mm | Comfortable |
| 7.5 in 19.1 cm | 59 mm | Comfortable |
| 8 in 20.3 cm | 63 mm | Comfortable |
Check it against your own wrist An estimate, not a guarantee; how the method works is on the tool page.
What the research found
These are the research’s judgments, scored against Holden’s priorities, not his own words.
Strengths
- Slimmed 12.3 mm case fixes the old Samurai's bulk while keeping the angular identity
- Genuine Seiko design language — sword-like geometry, no homage debt
- 200 m diver's spec, screw-down crown, lumed bezel, bracelet with diver extension at a fair price
Weaknesses
- Hardlex rather than sapphire at $595
- Stamped clasp below the case's standard
- 4R35 entry calibre with 41 h reserve
- Long 49.5 mm lug-to-lug on paper (mitigated by lug design)
Research scores, 0 to 10
| Execution and feel in the hand | 6.5 |
|---|---|
| Design identity | 7.5 |
| Value at a realistic price | 7.0 |
| Long-term ownership | 6.5 |
| Movement and engineering | 5.0 |
| Wearability and proportions | 7.0 |
| Versatility and durability | 7.5 |
| Fit with Holden's collection | 7.5 |
Also on Holden’s list
Other diver watches on his list.
- Tudor Pelagos LHD 25610TNL-0001
- Grand Seiko Spring Drive U.F.A. Ushio 300 Diver SLGB023
- Traser P67 Diver Blue 109375
- Squale 1545 Grey 1545GG.AC
- Glycine Combat Sub 42 GL0533
Sources
- SRPL51 — official product page seikowatches.com · read August 26, 2026
- Seiko Samurai Review: Smaller And Better Than Ever teddybaldassarre.com · read August 26, 2026
- Seiko Prospex Samurai Diver SRPL51K1 — Chrono24 reference page chrono24.com · read August 26, 2026
- Seiko Prospex 42mm Samurai Automatic Diver with Blue Dial #SRPL51 longislandwatch.com · read August 26, 2026
Personal research, not a source of truth. Spotted an error? Email a correction.