Here's something you don't see every day - a brand new closure system in alpine ski boots hasn't really happened since Henke introduced the first buckle boot back in the 1960s. The Salomon S/Pro Supra BOA 105 Ski Boots not only rock the new Boa®, which brings a new level of comfort to wider feet and taller insteps, but instead of leather they are built of Custom Shell HD heat-moldable Polyurethane, making a whole new world of custom fitting available to skiers with anything but average-shaped feet. The S/Pro Supra Boa® 105 has the perfect flex for advanced to expert skiers who don't need the stiffest boot out there and want a versatile, all-mountain/all conditions flex. Product Details Fit Last:100 mm – Average last intended for medium width and volume feet; can be successfully adjusted for wider feet with the Custom Shell HD heat molding process. Custom Shell HD – Salomon's proven heat molding process makes boot fitting most feet quick and easy - the latest Custom Shell HD version is even quicker to mold than before. The thinner wall construction and new shell materials allow the foot to be closer to the shell and provide enhanced sensations, more power and direction energy transmission. Flex Flex: 105 – A stiff flex suitable for advanced to expert skiers Liner My Exowrap™ 4D Perf Liner Custom Tongue Shell Materials & Design Cuff – Polyurethane with Custom Shell HD and Power Spine Shell – Polyurethane with Custom Shell HD and Sensifit Mesh Buckles 2 Screwed Aluminum – Tool-free fine tooth adjustment Boa® Fit System Lower Closure – Quick and easy dial-up adjustment to tighten or loosen tension, plus pullout to completely loosen cable. (Note: Left boot tightens by turning the dial counterclockwise). Power Strap 45 mm Screwed Energy Z-ER Velcro – This easy to remove 45 mm thick strap holds the lower leg securely in place and optimizes power transmission, while an elastic section enhances rebound and progressiveness. Bootboard & Footbed Light² Footbed Sole GripWalk ISO 23223 Walk Soles