Fins, for swimming, diving to provide a strong forward momentum, the wide area of the fins can provide a strong power, not rely on the hands to create momentum, so that the hands can be liberated to engage in other work.
The fins are divided into two types: heel and sleeve. Foot flippers are generally used in warm waters or snorkeling. No heel fins to be used with the diving boots. Large, hard fins are used quickly, but easily fatigued and cramped, and small, soft fins lack the power to push.
Fins have different materials, designs, and features. Fins are designed to include a keel to increase the stiffness and balance of fins, drain holes, and reduce resistance to fins to increase efficiency; Choosing fins depends on your body size, physical strength and diving environment, and it is important to be comfortable and fit.
You can use the back heel to adjust the tightness, but you need to put on the diving socks or diving boots in order not to pressure the foot in the water during the kick.
Full-pack foot fins
Simply put the fin on your feet and do not need to buy any extra diving boots. The advantage is light and cheap.