The Apple Watch Sport Loop band was woven from nylon thread to create a hook-and-loop closure. These bands were available for the 38/40mm and 42/44mm Apple Watch models, and were offered in a size to fit 130–190mm wrists.
Beginning around 2018, Sport Loop designs were comprised of a base color and one or more accent colors. This Kumquat band uses an orange base color with edges accented in dark green and dark blue. In addition, the plastic connectors are orange while the closure plastic is dark blue.
Apple described the Apple Watch Sport Loop band:
“Soft, breathable, and lightweight, the Sport Loop features a hook-and-loop fastener for quick and easy adjustment. The double-layer nylon weave has dense loops on the skin side that provide soft cushioning while allowing moisture to escape. On the reverse side, the attachment loops are securely anchored for superior durability.”
Beginning in 2020 Apple began including a Band Compatibility statement on its website:
“You can match most bands with any Apple Watch Series 3 or newer case of the same size. (For Apple Watch Series 3, the 40mm band works with the 38mm case; the 44mm band works with the 42mm case.) The Solo Loop and Braided Solo Loop bands are only compatible with Apple Watch SE and Apple Watch Series 4 or newer. The 40mm case works with band sizes 1–9; the 44mm case works with band sizes 4–12.”