Never Worn This Hydroknit Band is perfect for water sports, high sweat activities, or showering; retains “30%” less water. Includes the Fast Link Slider making it faster & easier to change bands. Compatible: WHOOP 4.0 Includes: BAND ONLY - band - hook - clasp - fast link slider Color: Tidal (vibrant blue) & black components Materials: - band: microfilament yarn - clasp: stainless steel - hook: stainless steel - fast link: stainless steel Size: Band Length: 9.5 in/24cm One Size Care: Handwash w/ mild soap, cold water, air dry only