Size Guide:
Apple Watch Series 1 and Series 2:
Apple Watch Series 3:
Apple Watch Series 4 and Series 5:
Apple Watch Series 6 and Series 7:
Apple Watch Series 8 and Ultra:
Compatible with 41mm bands (40mm bands also compatible, but may not fit as snugly)
Compatible with 45mm bands (44mm bands also compatible, but may not fit as snugly)
Apple Watch Ultra is also compatible with 49mm bands, which are designed for use with Apple Watch Ultra
Note:
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