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 sizes to fit 130–200mm wrists (40mm) and 145–220mm wrists (44mm).
This Neon Lime band used two base colors of dark blue and denim blue. Both edges were accented in neon lime green. The plastic connectors and closure were 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.”
Source: Apple
