The Nike Sport Loop band was woven from nylon thread to create a hook-and-loop closure. These bands were available for the 41mm and 45mm Apple Watch models, and were offered in sizes to fit 130–200mm wrists and 145–220mm wrists . The bands also fit older Apple Watch sizes of 38mm/42mm and 40mm/44mm.
This Black band used a base color of black (it could also be called dark gray) and had the word NIKE woven into the design around the outer band and the NIKE “swoosh” on the part of the band with the hook-and-loop closure on the back. The connector plastics were black to match the base color of the band.
Apple described the Nike Sport Loop band:
“Breathable and lightweight, the Nike Sport Loop is designed for fitness. It’s made from a soft nylon weave featuring the iconic Nike swoosh. A hook-and-loop fastener makes for quick and easy adjustment, and dense loops on the skin side provide soft cushioning while allowing moisture to escape. On the reverse side, the attachment loops are securely anchored for superior durability.”
Source: Apple