An adjustable strap attached to the back of the shoe that wraps around the ankle.
About Zip Up:
Zip up describes articles that are fastened with a zipper, for example, a zip up jacket. The zipper mechanism uses two separate strips of fabric with interlocking teeth called chain zippers and a slider with a tab to open or closed the strips. Zippered closure is practical, fast, and secure; as a result, it is widely used in a variety of articles including bags, shoes, apparel, and small leather goods.