Nike Men's Dri-FIT Flash Running Tights, Black/Reflective Silver, Medium Elastic waist with interior drawcord and stretch fabric for a snug, contoured fit Flat seams are ergonomically positioned to reduce chafing and increase comfort. Reflective details for enhanced visibility in low-light conditions and a zip pocket at back for secure storage of small items Zipper leg openings allow easy on and off Machine Wash: 85% Polyester 15% Spandex