Coolibar UPF 50+ Men's Super Sport Hat - Sun Protective 100% Polyester Hook and Loop closure UPF 50+ - protects against 98% of UVA and UVB rays Elastic Velcro closure in back for a custom fit; Removable neck flap allows you to customize your coverage; Travel friendly packable construction Lite SUNTECT: Ultra-soft with a cotton like feel, lightweight, breathable, quick dry performance; Approx. Circumference (S/M) 22 3/8 inches (L/XL) 23 inches; 4 inch brim Hand wash; Imported The Coolibar ULTIMATE COVERAGE Collection indicates styles used to cover the majority of your skin with UPF 50+ protection. No one piece of clothing can prevent sun damage, but by combining pieces from the ULTIMATE COVERAGE Collection, you can effectively cover 90&percnt; of your exposed skin while blocking 98&percnt; of UVA/UVB radiation.