Our new double-strap version of the popular Zong, the Zong-X offers added comfort by conforming to the subtle curvatures of your foot. Features: Double-strap Zong-X conforms to variations in feet Toe-wrap for side-side forefoot stability 360 Wrap-Fit adjustable straps BioCentric footbed with PU formulation oriented towards out-of-box comfort EcoTread outsole features 25% recycled rubber