Adult Modular Motorcycle DOT Dual Visor Full Face Flip-up Helmet Black Medium Retractable tinted sun visor Smooth opening and closing with easy to actuate button Advanced front flow ventilation system with channels for maximum venting and comfort Please measure for size. Each manufacturers sizing is different. 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. Unlike most online sellers we allow you to exchange your purchase 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. Retractable tinted sun visor for added convenience Smooth opening and closing modular design Removable &amp; washable cheekpads Sculpted aerodynamic ABS shell offering a sleek and lightweight design Advanced front flow ventilation system with channels for maximum venting and comfort Standard D-Ring closure chin strap Take a head measurement with a cloth tape measure. Wrap the tape measure around your head one inch above your eyebrows, directly above your ears and to the widest area at the back of your head. This will give you the circumference, which is the measurement displayed below.