Adult Dual Visor Modular Full Face Snowmobile Helmet With Heated Shield, Breath Box (White, Small) Heated electric shield with cord included Retractable tinted sun visor Smooth opening and closing with easy to actuate button Adjustable breathbox and chin skirt included SIZE CHART (Circumference of the largest part of your head, usually just above the eyebrows) in inches SMALL: 21  to 22 - MEDIUM: 22 to 22  - LARGE: 22  to 23 - XL: 23 to 23  - XXL: 23  to 24. Head shapes can affect how a helmet fits. The size chart is meant to be a starting point. Typhoon Helmets allows exchanges for a different size or color. Just return your purchase to us at your expense and we'll send your exchange at no charge to you.