Martin Natural Navy Slip On Mule The Martin Mule is HEYDUDE’s relaxed slip-on backless mule style. An easy wear staple style, essential for all down time at home or away. Lightweight traction sole and antibacterial memory foam insoles make it perfect for all environments. Style features include a natural organic cotton upper, finished with a raw edge, sewn over seam. Includes cork-lined, memory foam insoles with antibacterial properties. Features: Organic cotton material Relaxed fit Ridgelight sole unit Weight 150grms Ultralight outsole Machine washable cold Cork -lined, removable anatomic insole