swimfins, swim fins, fins or flippers are worn on the foot or leg , made from rubber or plastic and shaped like fish fins, to aid movement through the water in water sports activities.
Scuba divers use fins to move through water efficiently, as human feet, being very small, provide relatively poor thrust, especially when the diver is carrying equipment that increases his drag in the water. Very long fins and monofins (one big fin) are used by freedivers as a means of underwater propulsion that does not require a lot of leg movement.
Who thought this stuff up?
Early inventors, including Leonardo da Vinci and Giovanni Alfonso Borelli (mathematician, physiologist, and physicist) toyed with the concept of swimfins.
It is said that Benjamin Franklin made a pair of early fins when he was a young boy living in Boston, Massachusetts near the Charles River. They were made of two thin pieces of wood, about the shape of an art palette, which allowed him to move faster than he usually did in the water.
Modern swimfins are an invention from the Frenchman Louis de Corlieu, a Lieutenant Commander in the French Navy. In 1914 De Corlieu made a practical demonstration of his first prototype for a group of navy officers, Yves le Prieur was among them, who years later, in 1926, invented an early model of scuba set. De Corlieu left the French Navy in 1924 to fully devote himself to his invention. In April 1933 he registered a patent (number 767013, which in addition of two fins for the feet included two spoon-shaped fins for the hands) and called this equipment propulseurs de natation et de sauvetage (which can barely be translated as “swimming and rescue impulse device”).
After floundering for years, even producing his fins in his own flat in Paris, De Corlieu finally started mass production of his invention in France in 1939. The same year he rented a licence to Owen P. Churchill for mass production in the United States. To sell his fins in the USA Owen Churchill changed the French De Corlieu’s name (propulseurs) to “swimfins”, which is still nowadays the current English name. Churchill presented his fins to the US Navy, who decided to acquire them for its Underwater Demolition Team (UDT). American UDT and British COPP frogmen (COPP: Combined Operations Pilotage Parties) used the “Churchill fins” during all prior underwater deminings, allowing this way in 1944 the Normandy landings. During the years after World War II had ended, De Corlieu spent time and effort struggling with civil procedures, sueing others for patent infringement.
In Britain, Dunlop made frogman’s fins for World War II, but after the war saw no market for them in peacetime, and, after the first supply of war-surplus frogman’s kit was used up, the British public had no access to swimfins (except for home-made attempts such as gluing marine plywood to gymshoes), until Oscar Gugen began importing swimfins and swimming goggles from France.
In 1946 Lillywhites stores imported about 1100 pairs of swimfins; they all sold in under 3 months.
In 1948 Luigi Ferraro, collaborating with the Italian diving equipment company Cressi-sub, designed the first full-foot fin, the Rondine, named after the Italian word for swallow. A distinctive feature of Cressi’s continuing Rondine full-foot fin line is the embossed outline of the bird on the foot pockets and the blades.

In 1949 Ivor Howitt or a friend of his sent a letter to the Dunlop Rubber Company for swimfins; Dunlop answered that they had no plans to make swimfins and saw no use for them in peacetime. Howitt , therefore, made his own swimfins with inner tube rubber stretched across a frame of stiff rubber tube.
Types of fins… keeping everyone happy.
There are a multitude of fin types and shapes designed to suit the variety of sportmen that use them. Scuba divers, in particular, need large wide fins to overcome the water resistance caused by their diving equipment; snorkelers need lightweight flexible fins; ocean swimmers, bodysurfers, and lifeguards favor smaller designs that stay on their feet when moving through large surf and that make walking on the beach less awkward. In general there are two main groups of fins; full foot and open heel. Full foot fins fit like a shoe, and are designed to be worn over bare feet. If a larger size is chosen, however, full-foot fins can also be worn over socks and thin-soled booties. They are commonly used for surface swimming, and are in non adjustable sizes. Open heel have a foot pocket with an open heel area, and the fin is held to the foot by springs or straps. They can be worn over boots, and are common in diving. Many companies design fins with the same fin architecture but a choice of heel type. Other, more specific design trends are listed below.
Common types
Paddle fins
These are the most basic fins; a pair of simple stiff plastic, composite, or rubber blades that work as extensions of the feet while kicking. Some paddle fins have channels and grooves to improve power and efficiency though it has been shown that the desired effect does not occur. Paddle fins are widely believed to be the most versatile and have improved swimming economy in men. Tests in women showed a more flexible fin to be more economical, most likely due to lower leg power. We have a variety of this style of fin to suit everyone’s needs at the Davy Jone’s Locker Retail shop.

Vented fins
Vented fins were first designed in 1964 by Georges Beuchat and commercialised as Jetfins. The Jetfin trade name and design were sold to Scubapro in the 1970’s. This style of fin is strongly favored by technical divers that use a frog kick allowing a high degree of control but sacrifice speed for low oxygen consumption. Vented fins are generally stiff paddle fins that have vents at the base of the foot pocket. The vents are intended to allow for the passage of water during the recovery stroke, but prevent passage during power strokes due to the blade angle, attempting to lessen effort during recovery and improve kick efficiency. A review and study by Pendergast et al in 2003 concluded that vented fins did not improve economy, implying that water does not pass through the vents. For the diehard techie, Jetfins are available for purchase at the Davy Jone’s Locker retail shop.
Split fins
Some swimfins have the end of the blade split. The manufacturers claim that split fins operate similarly to a propeller, by creating lift forces to move the swimmer forwards. The claim is that water flowing toward the center of the fin’s “paddle” portion also gains speed as it focuses, creating a “suction” force. A 2003 study by Pendergast et al called this into question by showing that there was no significant change in performance for a particular split fin design when the split was taped over. The technology used in most commercial split fin designs is patented by the industrial design firm Nature’s Wing, and is used under license. Personally I am starting to think that Pendergast et al liked having the bits of wood strapped to their gymshoes!
Freediving fins
These are very similar to paddle fins, except they are far longer, and designed to work with slow stiff-legged kicks that is supposed to conserve energy. The vast majority are made in the “full-foot” design with very rigid footpockets, which serves to reduce weight and maximize power transfer from the leg into the fin. Freediving fins are commonly made of plastic, but are also often made from materials such as fiberglass and carbon fiber.
Monofins
A monofin is typically used in finswimming and free-diving. It consists of a single surface attached to footpockets for both the free-diver’s feet. Monofins can be made of glass fibre or carbon fibre. The diver’s muscle power and swimming style, and the type of activity the monofin is used for, determine the choice of size, stiffness, and materials.
And then there are the “special” fins:
Fins are generally open or closed heel, however the blade architecture can vary and there are always new inventions. These include (these names are trade names):
Delfins
The Mor-Fin Corporation produces “delfins”, which are swimfins that end short and to the end is attached a shape like a fish’s forked homocercal caudal fin. The entire fin is based on the anatomy of various marine animals.
Force fins
“Force Fin” is the trademark for fins designed, developed, manufactured and distributed by Bob Evans Designs, Inc. There are over 30 models of Force Fins. They are distinguished by an open foot pocket, that encloses only the instep, leaving the toes free so the foot can flex.
Shinfins
These fins are attached to the ankle and rest against the (anatomically) upper side of the foot. The manufacturers claim this avoids leg cramps and reduces foot strain.
Flipfins
Flipfins are a open-heel swimfin designed to allow easy walking on land. Its blade and foot part are separate: the blade hinges onto the foot part at each side, roughly on the level of the metatarsal heads, and when swimming is held in line by a clip on the front of the foot part. On land or when wading the blade can be unclipped and hinged vertically so it does not interfere with walking.
Breast stroke fins
Breast stroke fins are optimized for use with the breaststroke.
Swimming with fins during diving.
The PADI openwater course teaches new divers to use a flutter kick . Its different from the short , quick swimming kick , without fins. With fins the kick is slowed and the stroke is lengthened. The fins are pointed out behind the diver and the movement comes primarily from the hip. The knees should only bend slightly. Bicycle finning (looks like the diver is trying to pedal a bike) is inefficient and wastes the diver’s energy, adding to stress. If you are looking for your own set of fins, come into the retail shop and chat to us, we have a huge variety to choose from and loads of advice to help you make the best choice!
p.s. don’t use the term ‘flippers ‘ in front of your dive instructors.. you will be told that Flipper was a dolphin movie…