Made from a custom high-performance fluoroelastomer, the Sport Band is durable and strong, yet surprisingly soft. The smooth, dense material drapes elegantly across your wrist and feels comfortable next to your skin. An innovative pin-and-tuck closure ensures a clean fit. S/M - Band fits 130 to 180mm wrists Apple Watch Models - 38mm, 40mm, & 41mm The box has never been opened.