The Salomon Impact 8 CS ski boots offer you personalized comfort as you shred through expert level terrain. When heated, the Kaprolene™ shell forms to the exact width of your foot, maximizing comfort and performance. Kaprolene performs identically to standard polyurethane plastic used in most ski boots, except that it becomes pliable when heated. Heat boots, step in, let them cool, and enjoy a personalized fit that responds instantly to your movements! Custom shells should be molded by a professional boot fitter contact your local REI store for more information. Spaceframe Shell Profile, with multilayer construction and precise wall thickness, optimizes feeling, performance and energy transmission. Energyzer shell reinforcement in heel provides a progressive and responsive flex. My Customfit Sport liner, featuring a layer of conformable foam, personalizes the fit around the heel and the front of the ankle. Sensifit™ 2D cuff uses the same soft material in the shin and cuff overlap areas to accommodate varying lower leg shapes. Neoprene toe box absorbs shock and increases insulation. Loop on tongue aids putting the boot on and taking it off. Microadjustable titanium buckles shave weight off the boot while providing performance enhancing stiffness. Auto 3D instep buckle has 3 adjustable positions on the shell, allowing a personalized closure angle for optimal envelopment, comfort and control. Extended cuff buckles require less effort to close than standard buckles. 35mm strap enhances wrap and support of the upper ankle while increasing the boot's forward rigidity. Canting adjustment aligns the cuffs to lower leg shape rear spoiler heights can be adjusted for more or less rear support. If pressure becomes too great along the back of the calf, simply adjust the rear spoiler to fine tune your comfort.