The Mach1 HV 105 W is a high-performance ski boot specifically designed for strong female skiers. Fit is priority number one and an anatomically shaped high volume shell and a women's specific liner with Custom Adaptive Shape - C.A.S. - technology, provides a great fit right out of the box. T-Drive technology allows the boot to function more efficiently, resulting in a smooth, consistent flex and better performance while using less energy for all day performance.