Vasque's has raised the standard for mountaineering boots with it's new ICE 9000 by significantly lowering the weight and bulk of this new winter and expedition boot and adding key performance features. Weighing in at 4 lbs 12 oz (size 40) this boot will feel more like a lightweight trekking boot than a traditional double boot while delivering all the cold weather protection you need for high altitude summits. Less weight equals less fatigue, more climbing power and increased range. Composite construction blends Pebax molded lacing "fingers", full length carbon fiber lasting board, stretch Cordura tongue and the first ever STEALTH RUBBER Skywalk Fitzroy lug sole into an incredible package. Exo-Therm Inner Boot is a proprietary combination of thermoplastics, Kevlar nylon mesh, Mylar and Aveo Foam - more waterproof than leather, more flexible than plastic and warmer than both. Imagine how toasty good your feet will feel.