The Lange SX 90 makes a perfect boot for the strong intermediate to advanced skier that has a medium to narrow forefoot and medium to narrow leg shape. Lange's Polyether Shell does a great job keeping a consistent flex regardless of how warm or cold the outside temperature is. The SX 90 is made with a Natural Stance that is more upright with a four degree ramp angle that provides you with more control and requires less energy to make modern skis with rocker and sidecuts react when and how you want them to. Lange's Control Fit Liner has an Instep Pocket that allows your blood to flow easier to your toes, to keep you warmer. A Seamless Toe Box and Anatomically correct padding provide you with a strong heel hold and comfortable toes for all day comfort on the mountain. The SX 90 has a 35mm Power Strap that improves your leverage and control over your skis, and allows you to bend and flex the boot easier. If you are a strong intermediate to advanced skier looking for a medium to narrow fit, in both the forefoot and leg, the Lange SX 90 is your boot.