Bands for 38mm, 40mm and 41mm conditions are appropriate with each other, and bands for 42mm, 44mm and 45mm scenarios are appropriate with one another. Nylon is a good selection for a comfortable band, especially if you search for an Apple Watch strap created from super delicate nylon. Nylon bands https://allhealthmarket.com/product/aeahmarket/appleband/business-real-leather-loop/retro-leather-strap-band-for-apple-watch-series-ultra-8-7-6-5-4-se-42-44-45-49mm-bracelet/