This full length, full width, full strength carbon-fibre frame is thin yet rigid for crampon safety, with an excellent weight to strength ratio and less cold contraction than other materials.


Stiffness: 4/4



Made of nylon and fibreglass, it is the lightest frame in the family, thanks also to the grid design which removes unnecessary weight while maintaining structure. Strong enough for flexible crampon use, stability rearfoot and midfoot for heavy loads, but with enough forefoot flex for walking moderate distances.


Stiffness: 3/4



Full length, full width, full strength tapered nylon delivers the appropriate blend of stability and flexibility to haul heavy loads for a long distance in comfort. The tapered forefoot delivers a round, arcing flex, thus providing a flex range rather than a single point. This functions better at accomodating a variety of foot and toe proportions, flexing where the foot wants, rather than a predetermined single point where the boot wants to flex.


Stiffness: 2/4



Lightweight, full length, full width nylon frame. The rearfoot is bolstered with a thickened center zone. The forefoot flex is enhanced by medial lateral slashes which cross at an anatomical angle.


Stiffness: 1/4