There’s no question - no two heads are the same, but with ZoneFlex you get a contoured comfortable fit no matter how your dome is shaped. Add in the Ride audio capabilities and passive venting, and you have all the elements to protect your head in style and comfort with the 2012 Ride Duster Helmet. S = 54-56 M = 56-58 L = 58-61 Weight: 502g
