Zking Extreme Condition Sun Boonie Fishing hat Stone 60% Cotton and 40% Polyester Inner Diameter measures 7 1/2"(circumference 23), Brim measures 2 1/2" Wide, Crown measures 3 1/4" High One size fits most, adjustable chin strap, twill washed design Ventilation side holes for good breathability, crushable, packable, great for travel This hat is ideal for fishing, hunting , beach ,hiking ,gardening or any outdoor activities and sports