Nike Men's Dri-Fit Pro Combat Hypercool Baseball Shirt MLB 100% Polyester Machine Washable The Nike Pro Hypercool Men's Baseball Shirt features Dri-FIT fabric and mesh panels for superb comfort and breathability at practice and during training. Dri-FIT fabric helps keep you dry and comfortable. Mesh panels help keep you cool. Flat seams move smoothly against your skin. Ergonomic seams and stretch fabric enhance your range of motion. Fabric: Back panel: Dri-FIT 100% polyester. Mesh: Dri-FIT 93% recycled polyester/7% spandex. Body: Dri-FIT 92% polyester/8% spandex.