Smooth-button Rogrr Vivier's new Viv' Go-Thick metal buckle mules are inspired by the punk style of the 1950s. They are handmade with leather, embellished with rounded metal buckles, and have grooved stripes on the thick soles. They are fashionable and comfortable, showing Vivier. Personality. Upper: cowhide/smooth buckle Inner: sheepskin Code number: 35-39 (40/41 customized),