Chaco Women's Z1 Classic Sandal AllEars.Net Chaco Chillos Women's Sport Sandals Aqua Gray Outsiders Store UK Chaco Z1 Classic Sandals (For Women) Save 23% Chaco Z1 Classic Sport Sandals (For Women) Save 55%. History has it that when Mark Paigen designed and made the first Chaco sandal, a French friend described it as Zee One and so that style became the Z 1. That sandal became an icon, renowned for its durability and comfort, ensuring it a dedicated following. With a reassuring weight, this sandal is deserving of its title as an original, whilst being extremely comfortable; developed to support your feet on any terrain. Here at Outsiders, weve never worn a more comfortable sandal, I suppose you could count us amongst the converted.