NIKE Feather Light Cap (One Size, Red) Four black mesh vents for visual and functional flavor, black underbill and binding on all styles minimize visual glare and hooks it all together. Vents: Dri-FIT 100% polyester circular knit mesh. Quick-adjust back closure for secure, one handed on-the-fly adjustability. Sweatband: Dri-FIT 90% polyester/10% spandex terry. Body/bill: 100% recycled polyester plain woven