Features1Made of cooling ice silk,soft, stretchy,smooth and will not irritate your skin. 2Easy to clean and flexible to wear. 3Vent holes for breathable and refreshing wearing. 4Suitable for Cycle,running,hiking,climbing,playing tennis, dancing etc. 5Head circumference: 54-58cm / 21.3-22.8in.SpecificationFeatures:Made of cooling ice silk,soft, stretchy,smooth and will not irritate your skin. Easy to clean and flexible to wear. Vent holes for breathable and refreshing wearing. Suitable for Cycle,running,hiking,climbing,playing tennis, dancing etc. Head circumference: 54-58cm / 21.3-22.8in. Specification:Color: Dark gray / Light gray / Black (optional) Material: 90% Chinlon & 10% Spandex Head circumference: 54 - 58 cm / 21.3 - 22.8 in Cap circumference: 50 cm / 19.7 in Cap depth: 15 cm / 5.9 in Weight: approx. 25 g / 0.9 oz Package List:1* CapPackage List1* Cap