The comfortable baseball cap has an insulated crown and concealed Mackinaw wool earflaps lined with soft, brushed cotton. Sizes: Small: 6 3/4" - 6 7/8" Medium: 7" - 7 1/8" Large: 7 1/4" - 7 3/8" X-Large: 7 1/2" - 7 5/8" 2x-Large: 7 3/4" - 7 7/8"