Description from omegaaquatics.com:

Omega Aquatics manufactures and sells The Amphibian, the worlds first dynamic scuba fin, featuring our patented Aqua-Hinge technology.

A natural evolution within the dive industry, the Amphibian™ fin system is designed to be strapped on prior to entering the water and removed after exiting. The heavy-duty springs push the soft blade webbing up to ride gently against the shin while on the surface. This makes walking, climbing boat ladders and other movements as easy as wearing no fins at all. Once in the water, The Amphibian™ blades are flipped down into swimming position by simply kicking naturally in the water, and flipped back up by pushing back on the release levers before getting out.

Caravelle fins designed in 1963 "with a detachable polypropylene blade and foot pocket of rubber that essentially worked as galoshes. These rubber galoshes made it possible to walk to the shoreline, and then mount the blade onto the galoshes to continue diving

Ciamillo Propulsions Inc. introduces the first diver propulsor that taps into the grace and speed of dolphins

Patent 5429536:

A monofin comprising a swim blade having two adjustable foot pockets for attachment to the feet of a swimmer. The foot pockets can be positioned on the blade to conform with the optimal foot positions for a particular user. The blade itself has a central v-shape, so that when the foot pockets are attached to the blade each pocket leans inwardly towards the other. The blade has upturned outer wing sections to reduce the resistance during the retracting kicking motion. The blade is pitched to channel the flow of water rearwardly and centrally, focussing the water to a point behind the swimmer.

A swim fin (1) for divers or swimmers, having a freely leading profile (7) as the fin blade, which always has a positive angle of attack on both the upwardly (II) and the downwardly (I) oriented stroke of the fin with respect to the oncoming flow direction of the water, which is a product of the forward motion and the stroke of the fin, wherein to increase the propulsive action with simultaneously great freedom of motion of the diver or swimmer, the profile (7) is disposed downstream, in the swimming direction, of the foot (11) of the diver or swimmer and is always located in the undertow of the foot of the swimmer, whether the stroke of the fin is oriented upward (II) or downward (I).

A swimming apparatus for improved propulsion includes fluked foot flippers constructed to include a stiff load-bearing frame member in the leading edge of the fluke. As the flipper is pumped by the swimmer, a web secured to the frame member is caused to cup the flowing water by arching its surface. The flipper has the general shape of a porpoise tail and provides foot pockets adapted for fitting a variety of foot shapes and configurations.

Description from www.speedousa.com:

• Unique fin placement and design allows for uninhibited whip kick motion
• Provides similar thrust for whip kick as traditional fins do for flutter kick
• Comfortable foot pocket with open heel for better feel of the water
• Soft durable TPR material

Description from www.mor-fin.com:

Patented SCUBA FINS are now available with tail fins for moving through water just like fish. Using wing-like lift, they are more efficient and powerful

Description from eBay:

VARIABLE SPEED FINS (VSF) - Made in USA by Fluid Flight Company. VSF are versatile high performance fins that allow a diver to swim faster, further and with less effort than other high quality fins. Patended dolphin shaped blades give high thrust with minimum kicking effort. Blade angle is adjustable to low, medium and high speed settings for use as scuba or snorkel diving fins. Kicking effort can be adjusted to a diver's personal comfort level. Adjustable heel straps fit sizes 7 to 11. The fins are black with choice of red, yellow, green or blue racing stripes (specify when ordering). VSF have been sold to sport, cmmerical and US NAVY SEAL divers.

The all new fins Spider - a new product among Soprassub fins - these fins are unique in its design and material used ( thermoplast and rubber gum) and are made for snorkelling and freediving. The product boasts excellent dynamics with main benefit being that the spade remains under water surface at all times when snorkelling. Besides, thanks to different positioning of legs and spades virtually no whirling effect is created - that eliminates negative flow and water resistance when moving legs. Also, the new fins allow trouble-free walking on land.

New fin for spear fishing and free-diving, the pale's thick 'polipropilene' is in differentiated thickness. The down flow water holes have been improved by the patented system of adjustable analization. The slider has got three different positions to the rigidity adjust. The blade is made with three types of hardnesses: black, green and red are combined with shoes Master Pro.

Description from

MUSTANG project started early in 2002. My idea was not, as usual, to introduce a single evolutionary step to the product, like I did first using carbon fiber, then water–rails, innovative geometries and flaps. I decided to empty the project drawer of all the “sensible” ideas inside it and put them all in a new project. I had never done something like that with fins.

The technical purpose I had in mind was to improve fin performances climbing over real traditional limits, a jump to the future.

What are for me performances? They are the result of equipment usage on activities done by man with it.    ...  more

Description from www.apollosportsusa.com:

Apollo was the first manufacturer to visualize the benefits of 'propeller fin' technology. With any new technology a product must do more than just look and sound good.

The Bio-Fin had to stand up to our claims. After years of product development we introduced the first split fin in late 1998. The lightweight synthetic material was buoyant and fairly rigid. It could outperform any traditional paddle fin!

Our designers felt that the flexibility and lack of buoyancy inherent to rubber would make it even better. Six months later the original Bio-Fin Pro was introduced. It has been 'Tester's Choice' every year since 1999.    ...  more

Long history of performance. Considered the standard for power and durability since 1965.

Proven vented design. Decreases drag on the upstroke; enhances thrust on the downstroke. Adjustable heel strap. Secures strap for ease of pre-dive preparation.

Patented dual-directional water channeling system

1. Water flow directing scoop
2. Water channeling gills
3. Stabilizing wings
4. Compact blade design
5. Adjustable universal fin strap

Farallon, a company now defunct, produced the 'orthopedic fin.' A metal brace device was attached to the fin that extended up the diver's leg almost to the knee, where it was fastened with Velcro straps. The theory was that the brace took the pressure off the diver's ankle. It was a solution to which there was no problem, the most expensive fin of its era, and a major flop.

An updated version of our Foil Force twist your wrist and you can vary pitch of each Foil Blade to change its power output.

OPS, our Oscillating Propulsion System, attaches to our Launch Pad Foot Pocket. It has a long narrow blade that tapers to a point, to draw water similar to the way in which water wicks to the end of a leaf. When you kick it oscillates like an eel!

When locked into its flat position, the blade is flexible. Twist the blade at its point of attachment to stiffen the blade and shorten the oscillation for more sprint acceleration, when confronting current!

Force Fins with our side-supported for stability, adjustable over-the-top, toes-free foot pocket that reduces cramping and leverages power from your strongest kicking muscles.

Easy kicking, powerful and fast. Simply lift your foot to activate the SNAP of the blade and let the water accelerate through its split-V shape. Up-curved blade focuses water into thrust, instead of bobbing you up and down as when wearing flat fins.

Independently moving wing tips let you fine-tune your position in water with small foot and leg movements- just like the fish.    ...  more

These Easy kicking Force Fins feature a snappy scooped blade and ingtegrated, rigid, underside ribs that recoil and rebound to catapult you forward for maximum per-kick accleration.

Force Fins with our patented side-supported for stability, adjustable over-the-top foot pocket that adjusts down for a cushioned fit when barefoot, or up to fit over your wetsuit bootie.

Force Fins with our patented side-supported for stability, adjustable over-the-top foot pocket that adjusts down for a cushioned fit when barefoot, or up to fit over your wetsuit bootie or stocking foot wader.

Excellerating Force Fins feature our toes-free foot pocket that reduces cramping and leverages power from your strongest kicking muscles, for a most efficient and powerful kick. Clean edges that cut through the water without turbulence. A recoiling, ultra snappy blade designed to quickly move water behind. Vortex Generators keep water fast-flowing.

Excellerating Force Fins are adaptable for optional Force Wings (pictured with Whiskers), which allow you to control the way the water works for you. When positioned parallel to your direction of travel, they stabilize and track your fin.

When rotated inward, they accelerate water to the center and behind you, similar to the way in which water accelerates as it travels through a gorge.

Extra Force Fins feature our toes-free foot pocket that reduces cramping and leverages power from your strongest kicking muscles, for a most efficient and powerful kick.

Clean edges that cut through the water without turbulence. An ultra snappy blade designed to move a high volume of water behind, giving you maximum per kick acceleration.

Sculpted trailing edges and Vortex Generators keep water fast-flowing. Extra Force Fins are adaptable for optional Force Wings (pictured with Whiskers), which allow you to control the way the water works for you. When rotated inward, they draw water a large column of water to the center and behind you, accelerating it similar to the way in which water accelerates through a gorge, and create a ramjet effect to catapult you forward.

Force Fin's feature a toes-free foot pocket that reduces cramping and leverages power from your strongest kicking muscles, for an easy and powerfully efficient kick.

Easy to pack. Small, effective blade is the perfect size for turbulent free and fast movement of water. Easy to maneuver. Independently moving wing tips that let you fine tune your position with small foot and leg movements. Reduces chance of your kicking delicate marine life. Snappy, upcurved, split-V shaped blade channels water fast and with optimum directional control.

Slim Fins are the best all round swim fitness and swim training fin. They help you to burn more calories, increase swim fitness and conditioning levels, develop swim kick strength, improve body position and swim technique.

Slim Fins are great for snorkeling too!

Feature Force Fin's toes-free foot pocket that reduces cramping and leverages power from your strongest kicking muscles, for a most efficient kick. Easy to pack. Small, effective blade is the perfect size for turbulent free and fast movement of water.Easy to maneuver. Independently moving wing tips that let you fine tune your position with small foot and leg movements. Reduces chance of your kicking delicate marine life.

Tan Delta Fin Blade: A special Polyurethane, formulated to have the highest rebound, or snap.

Its the Snap of the Force Fin blade that channels water through the blade's split-V shape faster to maximize your propulsive efficiency.

Foil Force feature our patented upcurved blade that works with your most efficent and natural kick strength curve. Kick forward to activate the blade, let the snap of the blade catapult you forward and do the work for you on the recovery.

A power and recovery kick is more efficient than one with two way -- up and down -- stress.

Foil Force Fin's feature our toes-free foot pocket that reduces cramping and leverages power from your strongest kicking muscles, for a most efficient kick. Clean edges that cut through the water without turbulence.

I pondered how in the world he could ever do that. Being a nuclear physicist and a naval aviator, I knew a lot about forces, especially gravity and airfoils. I just had to dive into the explanation of this unreal phenomenon in depth. And depth was a big part of the explanation. I was told the tank was 60 feet deep. Looking through one of the underwater viewing windows, I watched this little guy swim along the bottom down to the lowest point of the tank, the drain. As he crossed it to go up the slope, he was already a blur. Suddenly he turned straight up so sharply that he must have pulled 9G's. in a flash he was gone.

Dolphin Man: Dolphfin

Design objectives

My aim was twofold, firstly see if a high aspect ratio fin would work better than the normal type and secondly use the beautiful dolpin whale fin shape.

What I found is that the swimming mechanism, is different from what dolphins and whales can do. The main reason for that is the amplitude you can make with your feet. It is much less than that of the aquatic mamals.

Also the fin will have to be very supple to flex when swimming, too stiff a fin does not work at all. This flexing requirement also means that the fin is very thin and has no profile section shape, as I would like to have.    ...  more

Description from www.abc.net.au:

Swimming — so graceful, so relaxing, so hard to break a world record. If only someone would invent a device you could attach to your body that would make you look really weird but help you swim a lot faster. If only.

US Patent 4944703:

A swim fin includes a foot receptacle for attaching to a swimmer or diver's foot. A pair of parallel beam supports are secured to the foot and toe portion of the foot receptacle and support a plurality of hydrofoil blades therebetween in a pivotal attachment. Limits are provided to restrict the pivotal motion of the hydrofoil blades to provide an optimum angle of attack for the hydrofoil blades during the swimming stroke.

Description from www.shinfin.com:

Swim fins for legsfreedom for feetshinfin swimming fins strap to legs not feet. Advantages over flipperscomfortable, feet are free, one size fits, streamlined kick, big muscle power, light & strong.

Eine Lösung zur ausgewogenen Fortbe-wegung im Wasser bieten die Armflossen Liquix™. In Kombination mit üblichen Taucherflossen für die Füße wird so der gesamte Körper mit in die Schwimmbewegung einbezogen.

Beim Schwimmen und Tauchen mit den Liquix™ Schwimmflossen wird der Wechselbeinschlag der Beine auf die Arme übertragen, wodurch sowohl Arm- als auch Brust- und Rückenmuskulatur gleichmäßig belastet werden. Der Schwimmer ist somit in der Lage, seine Schwimmstrecken auszuweiten und dabei wesentlich schneller zu schwimmen. Die Liquix™ Schwimmflossen stellen für Sportler wie Behinderte eine effektive Hilfe im Wasser dar. Die einseitige körperliche Belastung, die wir sonst vom Flossenschwimmen her gewohnt sind, wird vermieden.

Velosubmarine has high performances. It is going twice the speed than ordinary flippers, with hardly any effort ! Using a high tech composite propeller, it can reach 3 knots. It is also maintenance free, and safe: The propeller turns slowly and is moreover protected. If your are working in the aquatic leisure field, the VELOSUBMARINE will bring a great pleasure to your clients as well as a competitive advantage for you. Renting out VELOSUBMARINE will provide you profit in less than one season. What a sensation : Follow schools of fish effortlessly, swim alongside a coral reef, and admire the flora and fauna of the aquatic world ! Enjoy this unique underwater journey.

Inventor Bill Hopper has patents covering the innovative and unique characteristics of his invention. We know that dolphins create a "vortices trail" causing a "jet" or cut in drag at the end of each kick cycle. We are developing this technology into REAL PRODUCTS for various commercial applications.

From early tests we also know that FreedomFins absorb body drag further enhancing swim speed.

The result is greater kick-cycle efficiency using a shallower kick stroke, which reduces the physical energy required per unit of distance by the diver. FreedomFins attach to the lower leg thereby leaving the ankles and feet free for walking on land or in a boat upon entering or leaving the water. The leg attachment also reduces muscle strain and fatigue of the ankle and foot. The inherent design better suits the human anatomy by utilizing the strongest limbs and eliminating reliance on the weaker ones.