What band size does the Apple Watch Ultra use?

The Apple Watch Ultra has a 49mm case. Compatible band width: 49mm proprietary lug. First-gen Ultra (2022)

Are LDFAS bands compatible with the Apple Watch Ultra?

Yes — 4 LDFAS bands are available for the Apple Watch Ultra, each covered by a 2-year warranty.

Apple49mmLug 49mm proprietary lugApple Watch

First-gen Ultra (2022)

Grade 1 Pure Titanium (99.5%+) — aerospace-grade, feather-light and skin-friendly.
Precision fit — engineered to the exact lug geometry of your watch.
2-year warranty on every LDFAS band.

Which LDFAS bands fit the Apple Watch Ultra?: Yes. LDFAS lists 4 compatible bands for the Apple Watch Ultra: Le bracelet en titane LDFAS pour Apple Watch Ultra 2 49 mm – Boucle courbée.; Bracelet en titane LDFAS pour Apple Watch Ultra 3/2 49 mm – Boucle courbée (style rétro); Bracelet en titane LDFAS pour Apple Watch Ultra 3/2/1 49 mm – Boucle réglable SSR; Bracelet en titane ventilé LDFAS pour Apple Watch Ultra 2 49 mm – Bracelet sport SSR.
What band size does the Apple Watch Ultra use?: The Apple Watch Ultra has a 49mm case. Compatible band width: 49mm proprietary lug. First-gen Ultra (2022)
Are LDFAS bands compatible with the Apple Watch Ultra?: Yes — 4 LDFAS bands are available for the Apple Watch Ultra, each covered by a 2-year warranty.