The Balega Ultra Light No Show Running Socks offers a reinforced cushioned heel and toe for comfort and durability. The unique triple Y heel creates a heel pocket which in ergonomically formed to the actual shape of your heel. In essence this creates a more formed and deeper heel pocket for ultimate fit and comfort. Its broad elastic arch support in both the arch and ankle firmly keep the sock in place. The heel tab aids in preventing the sock slipping into your running shoe. Balega"s Left/Right construction method ensures the perfect fitting sock!