The Vortex does not have a boot. It only has an upper body member, stabilizing straps, and an elastic cuff. The stabilizing straps are the only materials that spiral around the foot inside the shoe.
Nylon stabilizing straps form a complete figure-eight to help stabilize the subtalar and talocrural joints. Stabilizing straps are angled at the attachment and contour around the malleoli for enhanced comfort and migration resistance.
Upper Body Member
Upgraded upper body member now has four eyelets and an internal plastic rib to better anchor the stabilizing straps around the malleoli and resist distal migration.