The Kai is the stiffest open toe performer in Ronix's line up and has the best in non-heat moldable memory out there. These affordable shred shoes have the same refined styling as Ronix's other performance orthotic boots. The shell of this boot was made from recycled PET - plastic water bottle material. The Ultralon New Zealand Foam Lightweight Stage 2 Liner is extremely comfortable and less prone to packing out. Double laces provide a more customized fit while the 3-D Molded tongue blends comfort and performance. Built-in J-bars improve heel hold and the Articulating cuff allows the boot to flex with the rider without boot distortion. Tool-less mounting hardware. Low friction eyelets. Eco Innovation design means there are no potentially hazardous PVC solvents. Sizes: Medium: 7.5-9.5, Large: 9-11.5, X-Large: 10.5-14.5.