Mares X-STREAM diving fins. Size: R (26cm-28cm) This is a top-of-the-line model that pursues ultimate comfort and efficiency. Using three types of high-performance materials, it achieves excellent performance and high durability. The "Super Channel Thrust" system creates optimal water flow and improves propulsion. The foot pocket has a new design with countless holes to release water flow and reduce resistance. Equipped with the "OPB system," you can move forward without loss even with a flutter kick. Thank you for viewing. Please consider this item, understanding that it is a used product.