Mares Avanti Pure Open Heel FinsAvanti Pure Open Heel Fins The Avanti Pure diving fins have a blade length ranging from 27 to 34. 5 cm depending on the size. The fins have an open foot pocket and are made of bi material. Thanks to the soft and comfortable foot pocket, they can also be used barefoot or with comfortable soft socks. They have guides for the elastic bands that prevent the foot pocket from rotating. Features: Bi material fin with open foot pocket Can be used with socks