The Air Jordan 21 (XXI) Low with White/University Blue/Metallic Silver colorway feature an all white leather upper with light blue accents. One of the most noticeable features of Air Jordan 21 cents constructed from mesh, which provide plenty of ventilation for the bearer's foot. There is a carbon fibre shank plate in the midsole, as well as an improved I.P.S. technology with interchangeable heel Zoom air pillars or encapsulated air pillars. It is not recommended that you play basketball in these, as they do not provide enough support around the ankle, and can cause severe ankle sprains. The Jordan 21 shoes was released on July 12, 2006.