both - GAO HARNESS BOOTS combines style and functionality with its sleek black design, PU and calf leather upper, and convenient back-zip feature. The eyelet with shoelace and 2 metal buckle locks provide a secure fit for all-day wear. Expertly crafted for durability and comfort. PRODUCT INFO Style #: GAB107-WP102-09090 Upper: 50% PU + 30% Calf Leather + 20% Rubber Outsole: 70% EVA + 30% Rubber