NIKE Men's Pro Cool Compression Shirt Tee Dri-Fit 92% Polyester/8% Spandex Dri-FIT fabric helps keep you dry and comfortable Flat seams move smoothly against the skin Ergonomic seam design follows the natural lines of the body for incredible comfort Back mesh panels offer superb breathability Dri-FIT Fabric : 92% polyester/8% spandex. Machine washable.