Constant refinement has created improved stability and a more secure heel fit. Specialized backcountry version has women's-specific fit for comfort and efficiency. Non-slip Backcountry sole supports in difficult terrain. Supportive external heel cap and 3-D cuff support and allow easy ski movements. Comfort Guard for warm feet: Inside the boot, a light, thin layer of water-repellent insulation material offers additional thermal protection in the forefoot and toe area to keep the skiers warm as they glide through the snow.