Adjustable fin for underwater swimming - has fin sole and heel in one piece with elastic sleeve sliding over to hold to foot

摘要

The swim fin, for diving or under water hunting, is made up of two parts. One part is a sheet of plastics material, in one size, that forms a fin (a) at the front and the sole (b) and the heel (d) at the back. An elastic sleeve (c) slides over the plastics sheet and holds the foot, adjusting to the length and width of the foot. The motive part of the fin is trapezoidal in shape and has a constant or increasing section.