La Sportiva - Lhotse GTX (Black) - Mens: The ultimate mountaineering boot for extreme and mixed conditions!; High ankle cuff height and contoured heel pocket combined with EZ Flex2 tongue and speed lacing hardware for a perfect fit. Automatic crampon compatible La Sportiva MPE outsole for excellent traction in all mountaineering conditions. MPE stands for Mountaineering Performance Evolution. This proprietary sole features a dual-density SBR design, an SBR Aircushion, self-cleaning lugs, and automatic crampon compatibility. 3mm Idro-Perwanger leather with large rubber rand and GORE-TEX lining that provides durability and protection in extreme conditions.