For the Series 4-6, case sizes were 40mm and 44mm, while the Series 0-3 were 38mm and 42mm ... is a velcro nylon strap that has increasingly become the standard issue Apple Watch strap.

Band sizes for 38mm, 40mm, and 41mm Apple Watch ... 10 small and large options use the same strap size. You can also use ‘regular’ Apple Watch bands on the Ultra model. These rules should ...