Size 61cm, with elastic in the back for adjustment. The following is quoted from the official website: All-weather ◎ Waterproof Warm Flap Cap, shutting out both rain and cold 2-WAY design for a wide range of situations ● Product Features ● ・Waterproof, so you won't get wet in sudden rain. ・Lower the fur part for cold protection. Soft and warm ear muffs! ・The fur part can be flipped up and fixed as a flight cap style. ・Perfect for winter cold protection in town use, as well as winter camping and outdoor activities! ・Also perfect for commuting to work or school by bicycle or motorcycle, outdoor work, events, and watching sports! Material Outer fabric: 100% polyester Filling: 100% polyester Fur part: 55% acrylic, 45% polyester Lining: 100% polyester