Custom Shell can be warm formed for an accuracy fit that different boots simply cant coordinate But this boot isnt pretty much solace the larger than average 24mm rotate joining the upper and lower segments of the boot gives control more space to work with on its way into your skis and the Twinframe2 Construction utilizes numerous densities of material in the shell to give you firm help where you require it and agreeable hold wherever else SPECSLast Width 106Skill Level ExpertFlex Stiff