ARAI IS THE ONLY COMPANY OFFERING MULTIPLE INTERIOR-FIT SHAPES TO BETTER ADDRESS THE INFINITE VARIETY OF RIDERS’ HEAD SHAPES AND SIZES. No one pays more attention to the subtle variations and infinite possibilities of the human head shape than Arai. Why? Because it’s the secret to getting the best comfort and fit. So for more than three decades, Arai has pioneered different shapes – and even different proportions within those shapes – in our various helmet models, working to offer a better fit for more people. The Defiant-X has Arai's INTERMEDIATE OVAL (IO) interior fit shape.* *A Helmet needs to be tried on in order to determine a proper fit.