Premium nylon, breathable, quick-drying, durable, lightweight and soft comfortable wear. UPF 50+ for ultimate sun protection, blocks 98% of damaging UVA/UVB sun rays. Breathable mesh sides for better air flow which makes your head staying cool on the hot days. ONE SIZE FITS MOST: Adjustable rear drawstring for snug fit. Built-in moisture wicking sweatband keep you cool in summer. Hat Circumference 21''-24" ; Hat Brim Length: 4.5" ;Unisex Design ,The back of the hat for the elastic fast buckle, Adjustable Fit To Average Adult Head. ADJUSTABLE DRAWSTRING: Adjustable chin drawstring for fixing the sun hat, especially in windy days. The long neck flap protect your neck from sunburn effectively. PACKABLE: The hat is foldable, it packs down to a compact size and easily stows in a bag, backpack, or luggage for your next travel adventure. VERSATILE & FUNCTIONAL: This fashion functional sun hat is the best choice for traveling and outdoor activities such as fishing, exploring, hiking, trail, camping, gardening, picnic, beach, canoeing, rafting etc.it is also a good gift choice for your friends and family. Neck Flap Sun Hat with Wide Brim - UPF 50+ Hiking Safari Fishing Caps for Men and Women