La Sportiva - Makalu Women's (Natural) - Women's: Made for mountaineering and heavy backpacking. Rollerball hardware and a locking D-ring allow independent fit in the lower and upper portions of the boot. Features an MPE sole. 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. MPE Sole is crampon compatible, deep lugged and tough as nails for years of service in the harshest conditions. Features a 3mm Idro-Perwanger leather with rubber toe rand for durability and protection in all mountaineering applications.