Material: High quality 100% Polyester Funtion: Quick dry hat for outdoor sport. Lightweight, Adjustable, Mesh, Soft and Breathable, Brim, Sun protection, 50+ Anti-UV. Adjustable unique buckle on the back, let you adjust as the size as your head size. Unisex and unisize: 55 - 60cm (21.6-23.6 inch ). One size fits most. Fit for big head and small head. Perfect for men women boys girls. Great for any indoor or outdoor activities: running, golf, tennis play,fishing, hiking, camping, travelling, hunting, surfing, gardening etc.