Nike Calm Men's Mules When it comes to these mules, it's all in the name. Take a deep breath and slip into a water-resistant, minimal design with maximum cushioning. The contoured foam cradles your feet to help keep them in place, while a heel strap can be removed for a versatile look. Comforting colors in muted earth tones complete the look. All of the style—none of the effort. It's time for some Calm. Upper and midsole are made from a single piece of foam for a soft, seamless feel. Contoured footbed has a subtle texture pattern for extra grip. Outer shell is made from foam that's easy to clean. Rubber outsole gives you excellent traction and durability. More Details Removable heel strap