Fin for swimmers has integral longitudinal channel, which opens during downward movement to increase blade size and closes during upward movement

摘要

The fin has a blade (2) connected to a foot (F) via a fastener (1). The blade has a longitudinal recess (29) to accommodate an upper part of the instep. The fastener is located at the end of the blade to fasten it to the foot above the joint, and there is holder (3) to fasten it to the front of the foot. Outer blade sides (28) extend in a longitudinal direction in a curve upwards away from the foot. A channel (5) is formed between a blade side and one side of the recess, which expands during a downward movement of the fin to increase blade size, and returns to its original shape during an upward movement. The fin is manufactured from a polymer material.