Tuga Adult Unisex Runners Sports Cap - UPF 50+ Sun Protection (New Sizing) Main: 100% Nylon. Accent: 100% Polyester. Imported. UPDATED SIZING: ADULT MEDIUM HAT (one size fits most) with head circumference of 22.5" inches. Please measure your head with a measuring tape for best fit PRODUCT FEATURES: Mesh vents for moisture control, adjustable fit with Velcro closure for a customized fit, built-in sweat band to keep you cool during your daily runs and for those hot summer days, Tuga logo at side LIGHTWEIGHT SUN HAT: Packable for easy travel and low maintenance, quick drying fabrics for ultimate comfort at the beach, pool, hikes, gardening, running, for tennis, and pretty much any outdoor activity EXCELLENT SUN PROTECTION: Our sun hat fabrics are rated UPF 50+ and provide maximum UV sun protection by blocking 98% of UVA + UVB sun rays, wet or dry; similar rating as SPF for sunscreens. Covered areas don't need sunscreen. SAFE FOR YOUR SKIN AND THE ENVIRONMENT: Tuga sports cap sun hats are made from fabrics that are free of sunscreen chemicals, great for sensitive skin. Our hats help reduce your sunscreen footprint.We make skin safe and reef safe products!