Seiko
Seiko Prospex Sumo Strap Size — 20mm Lug Width
The Seiko Prospex Sumo has a 20mm lug width, so it takes a 20mm watch strap.
Lug width20mm
| Lug width | 20 mm |
|---|---|
| Case diameter | 45 mm |
| Lug-to-lug | 52.6 mm |
| Thickness | 12.9 mm |
| Spring bar Ø | 2.5 mm |
| End type | Straight |
Strap styles that fit
- NATO / ZuluSingle-pass — always fits 20mm.
- PerlonWoven pass-through, 20mm.
- 2-piece leatherStraight ends fit flush.
- Rubber / siliconeChoose thicker straps for fat bars.
- Milanese / meshSlides to 20mm.
- Metal braceletNeeds 20mm model-specific end-links.
▲ Large lug-to-lug — check on small wrists.
Get the right strap
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Seiko Prospex Sumo — strap questions
What size strap does the Prospex Sumo take?
The Seiko Prospex Sumo has a 20mm lug width, so you need a 20mm watch strap.
Will any 20mm strap fit the Prospex Sumo?
Yes for straight-lug styles (NATO, leather, rubber). A metal bracelet needs 20mm end-links made for this model.
What spring bar size does the Prospex Sumo use?
Roughly 2.5mm diameter — these are thicker 'fat' bars, so heavier straps suit it best.
Is the Prospex Sumo good for strap swapping?
Very — with standard 20mm lugs you can switch between NATO, leather, rubber and mesh straps in seconds with a spring-bar tool.