Our Hyperdeep series of mask, snorkels, and fins feature our latest underwater innovations for improved safety, comfort, and clarity. The Adult Hyperdeep Fin includes patented technology for enhanced comfort and performance. The short tail fin acts much like a whale tale to create a stong drive forward while conserving energy. With soft heel straps and flexible foot pockets, this is sure to make your underwater adventures more enjoyable. The small/medium should fit most women, and the large/xlarge should fit most men. Made by Speedo, the world's #1 swim brand!..Read More