The K2 Men's Spyne 130 All Mountain Ski Boots are built with high-performance, hard-charging, all-mountain skiing in mind. It is the burliest ski boot in the line and comes in either a 100mm or low volume 97mm last for a precise fit. The revolutionary Energy Interlock and the PowerFuse SpYne ensures efficient power transfer, and the PowerCinch Strap and PrecisionFit INTUITION® liner ensure the SpYne 130 is designed to take on all you can throw at it. The PowerFuse SpYne maximizes fore/aft flex efficiency and lateral stiffness for sustained performance and responsiveness in all terrain. A rear co-injected "Y" shaped design that adds strength and power to the Energy Interlock and optimizes materials in the cuff and shell eliminates excessive vibrations in rough terrain.