Description of Chaco Zong Sandals If you define casual as a hike to the local farmers’ market or rock-hopping across a placid stream, the Zong calls your name. A thoughtful combination of free-heel convenience and Chaco's performance focused Z/2®, the Zong provides kick-on comfort while keeping your forefoot firmly engaged in the mission at hand (or foot). The NEW EcoTread™ outsole is made from 25% recycled rubber, reducing Chaco's impact on the environment. EcoTread™ is available in charcoal and chocolate to complement the new midsole colors. Available on Zong, Hipthong and Wrapsody styles. Features: EcoTread outsole Easily adjustable pull-through strap system Wrap-around toe design