What Our Gearhead(R) Experts Are Saying: "The Kilo XTR feels like the perfect balance for ski mountaineering-super light and mobile on the skin track, but with enough stiffness to really drive the ski on technical descents. The Ultralon liner molds perfectly to my foot, and the WarmSole Platform keeps my toes happy even on frigid belays." For ski mountaineers who want more power on the downhill without giving up uphill efficiency, the La Sportiva Kilo XTR Ski Boot delivers. A burlier evolution of the Kilo, it uses a Pebax(R) RNew tongue in the Force Flex System for a stiff, progressive flex that inspires confidence in steep, variable terrain. With a 68deg range of motion, it moves effortlessly on the skin track, and the Tilt-Lock Lite ski/walk mechanism transitions quickly and securely between modes. Inside, the Ultralon foam liner offers a customizable, thermomoldable fit with excellent insulation. The WarmSole Platform keeps feet separated from the shell for added warmth during cold-weather missions, while the Frixion Wave Alpine outsole provides grip and durability when booting up couloirs or scrambling rocky ridges. Built with next-generation bio-based Grilamid LF Carbon & fiberglass materials, the Kilo XTR balances stiffness, support, and weight savings for ambitious objectives in the high alpine.