Black Diamond Women's Stiletto Ski Boot Female-specific liner construction, spoiler and flex Triax Performance Frame with Flex 100 and MidStiff bellows Optimized ankle flexion for an ideal balance of cuff-to-bellows flex Women's Power Fit Light Liner features a 3: 1 Boa closure system, warm aerogel-insulated Strobel base and articulating zones for touring comfort 102 mm V-shaped last