NRS Havoc Livery Helmet Universal UV Swimsuits Ruffle. The NRS Havoc Helmet is your one size fits most solution to whitewater safety. NRSs DialFit system lets you quickly and easily adjust the fit to accommodate almost any head size. Protect nearly any adult with the same helmet. No more mixing and matching. Features The ratchet adjust DialFit system lets you custom fit the Havoc with the simple twist of a knob. Fits a range from 53 62cm (20. 86" 24. 4"). An adjustable chin strap ensures comfort and security. Plush FIT pads in key contact points provide extra comfort. FIT pads are fixed, so they wont get lost. If damaged, they are easy to replace. Ten ventilation drainage ports let air in and water out. ABS plastic shell is lightweight and durable. Glued in EVA foam liner offers excellent impact protection. Meets CE 1385 standards for whitewater safety. Not Logged in chrome chrome