Scuba flippers, or fins, are plastic or rubber shoes that are finlike and worn in the water. They are worn to assist the wearer in water activities, including swimming, scuba diving, free-diving and snorkeling. Fins are used to move faster and more efficiently in water.
There are a number of specialized flippers used for various water activities. Scuba divers, for instance, need larger and wider fins than swimmers and snorkelers, since heavy equipment slows down movement underwater. Snorkelers, however, need lighter and more flexible flippers to move freely at the surface of the water. Swimmers, lifeguards, and bodysurfers like to wear smaller flippers because they are less cumbersome on land.
Paddle fins are the most basic flippers. They are made of plastic or rubber material and serve as extensions for the feet. Most paddle fins have water vents around the blade to help the wearer move faster in water. Paddle fins are not the most efficient flippers, but are considered the most versatile.
Split fins are flippers with blades in the middle. The division at the center of the blade allows the user to move faster since the separated fins create propeller-like actions underwater. The flippers create a channeling or "scooping" effect that allows water flow through the blade for faster results.
Splits fins are among the most efficient. However, they cannot be used for frog kicks, and maneuvering with the flippers is difficult. Split fins, though efficient, are not necessarily versatile.
Force fins were created by the Force Fins Company. They have unique characteristics that allow the wearer to move more efficiently underwater. The blade of a force fin has a V-shape cut similar to the tails of some fishes.
Force fins, however, are criticized because they are hard to maneuver. They are usually not worn for scuba diving, since the negative buoyancy of the lightweight material partnered with the positive buoyancy of diving boots causes buoyancy problems. The condition is widely known as "floaty feet".
Freediving fins are like long paddles. The flippers work well with slow energy conserving leg movements. The flippers are available in a variety of kinds, including plastic, fiberglass, and carbon fiber.