Fabric:100%cotton; Lining:18%cotton/82%polyester. Imported UPF 50+ UV PROTECTION: the 3.3 brim blocks most sun UV rays effectively. FOLDABLE: packable, crushable, NO crease! Great for cruise, travel, gardening, boating or beach vacation. Lightweight and well ventilated to keep you cool in summer. CHIN STRAP: the detachable neck cord will keep hat stay safe on head in wind. Size Adjustable: 56-59cm 22-23.2 7- 7 3/8. Adjusts via string inside sweatband.