Casio
Casio F-91W Strap Size — 18mm Lug Width
The Casio F-91W has a 18mm lug width, so it takes a 18mm watch strap.
Lug width18mm
| Lug width | 18 mm |
|---|---|
| Case diameter | 38.2 mm |
| Lug-to-lug | 37 mm |
| Thickness | 8.5 mm |
| Spring bar Ø | 1.5 mm |
| End type | Straight |
Strap styles that fit
- NATO / ZuluSingle-pass — always fits 18mm.
- PerlonWoven pass-through, 18mm.
- 2-piece leatherStraight ends fit flush.
- Rubber / siliconeDivers & sports fit well.
- Milanese / meshSlides to 18mm.
- Metal braceletNeeds 18mm model-specific end-links.
▲ One-piece feel — single-pass straps work best.
Get the right strap
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Casio F-91W — strap questions
What size strap does the F-91W take?
The Casio F-91W has a 18mm lug width, so you need a 18mm watch strap.
Will any 18mm strap fit the F-91W?
Yes for straight-lug styles (NATO, leather, rubber). A metal bracelet needs 18mm end-links made for this model.
What spring bar size does the F-91W use?
Roughly 1.5mm diameter.
Is the F-91W good for strap swapping?
Very — with standard 18mm lugs you can switch between NATO, leather, rubber and mesh straps in seconds with a spring-bar tool.