MAIBU Unisex Adult Outdoor UPF 50+ Sun Hat Foldable Mesh Sports Cap 100% polyester, ultra lightweight, quick drying, soft and comfortable to wear Provides UPF 50+ sun protection, inhibits harmful UV rays Adjustable Velcro at the back; one size fits most with circumstance of 23.2 inches Foldable and packable brim design, convenient for storage and carrying when not use Mesh side panels for breathability and moisture wicking sweatband for keeping you cool and dry at hot summer days