The Zero Running Shoes are stripped down to what matters. Mesh covers the entire shoe including the tongue, so air flows through from every direction. MATERIALS & CONSTRUCTION Upper: Breathable mesh material across the sides, heel, and tongue. Outsole: Lightweight EVA (ethylene-vinyl acetate) sole built for flexibility and everyday movement. Insole: Cushioned EVA insole that absorbs impact over long periods of wear. Lining: Non-woven fabric lining for a smooth interior fit. Style: Low-profile running silhouette. Men's and Women's fit. Weight: 655g (Women's smallest) to 870g (Men's largest) PRINT QUALITY The print bonds directly into the material rather than sitting on top. It won't crack, peel, or fade with normal wear. High-resolution printing across every customizable surface of the shoe. Full color with no limit on the number of colors in your design.