The Omer Stingray foot pockets are manufactured with the newest rubber compression molding technologies existing today. The internal geometry of the foot pocket has been ergonomically designed to fit with total comfort. The foot pocket is produced with natural rubber in two different stiffness compounds throughout the different sections of the pocket to maximize the efficiency of the stroke without compromising comfort Available sizes: 5-6 (39-40), 7-8 (41-42),9-10 (43-44), 11-12 (45-46), 13-14 (47-48), 14-15 (49-50). These sizes reflect European and US numbers stated on the foot pockets. The European size is correct, but the US size may not be accurate. It's important to use the stated sizes as a reference to the foot pocket only, not necessarily as to how it fits. The Omer Stingray Pockets are sold individually.