Nike Calm Mules. Meet your new favorite travel companion. While these water-friendly mules are ideal for the beach or pool, their minimalist design is elevated enough to wear around in the city. Soft yet responsive foam means all-day comfort, while a removable heel strap lets you switch up your look. You get all of the style, none of the effort. 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. Removable heel strap. Imported.