F-91W Strap Size & Fitment
F-91W Strap Size — 18mm Lug Width
18mm (F-91W / A158 / A159 family) is the number that matters for the F-91W. The F-91W family shares one mount — straps and metal case kits both key off the 18mm lug width.
| Measurement | Value |
|---|---|
| Lug width | 18mm (F-91W / A158 / A159 family) |
| Adapter needed | No |
| Spring bars | Standard |
| Screen | 12×22mm |
What fits
FAQ
What size strap fits the F-91W?
18mm — direct spring-bar swap, no adapter.
Do A158 and A159 straps fit the F-91W?
Yes — the whole family is 18mm.
What is the F-91W screen size?
12×22mm — relevant for case kits and screen protectors.
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