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 PRODUCT(RED) band used two base colors of red and violet (with red accents). Both edges were accented in bright red. The plastic connectors and closure were red. As of 2021 Three Sport Loop PRODUCT(RED) designs had been released. This version is Generation 2.
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.”
As of 2021, Apple had been partnering with PRODUCT(RED) for 14 years. According to the dedicated PRODUCT(RED) web page:
“For 14 years, our partnership with (RED) has led to almost $250 million in donations to fund HIV/AIDS treatment programs. Now through June 30, Apple is working with (RED) to redirect 100 percent of eligible proceeds from (PRODUCT)RED purchases to the Global Fund’s COVID‑19 Response. This will provide critical support to health systems most threatened by the outbreak and, in turn, help preserve lifesaving HIV/AIDS programs in sub-Saharan Africa.”
Source: Apple (Sport Loop, PRODUCT(RED))