in Form Pro last delivers an ergonomically optimized, high-performance fit Stiff Silver Series carbon/fiberglass composite sole provides better power transfer Single Boa IP1 dial allows precise, two-way fit adjustments Stiffness index 1 of 14 Tachyon rubber outsole allows great grip in all terrains Perforated synthetic uppers allow increased breathability & comfort Asymmetrical design & superior lace routing system reduces top-of-foot pressure for a more secure fit Durable Gnar Guard outer material protects against abrasions & fights debris