104mm last: Comfort is key for skiers matching up to this last width. * 90 Flex rating: This boot has a flex rating in the intermediate to advanced range * Micro-adjustable aluminum buckles: These aluminum buckles can be moved to adjust for size, so if the default position of the buckle and the teeth is too wide or too narrow, you can move it until it fits. * 45mm Strap: Super wide strap found on high performance boots. The extra width spreads out the force while skiing and reduces the pressure point on the upper shin. * SensorFit Technology: Rossignol"s Sensor boots are anatomically designed to have direct contact with the foot"s "balance receptor points" (big toe, little toe, heel) to give a comfortable fit as well as greater power