There are primarily two types of fins: Open Heel (above left) and Full Foot (above right).

Full Foot fins have a closed foot pocket and are designed to be worn over bare feet. The blade of the fins are generally smaller in size, ideal for snorkelling and travelling. This style of fin is geared for use in warm waters.

Open Heel fins are required for scuba diving and can also be used for snorkelling. They are larger in size to provide propulsion with sufficient power to move the diver through the water with the added drag of the scuba equipment system. Because these fins are designed to be worn with boots secondary benefits include environmental protection of the feet. Diving boots have a sole to protect the foot and provide added traction while walking, entering the water, climbing up a ladder, etc. This is one of the reasons why snorkellers may prefer to use this style of fin. The neoprene upper of the dive boot also provides added warmth depending on the style and thickness.

Because open heel style fins are designed to be worn with boots, they are also too large for just bare feet. In general, Open Heel fins (also called Power Fins) can be used for snorkelling and diving, while Full Foots fins are geared primarily for snorkelling.

There is a third classification of fin usually referred to as a long blade style or a Free Diving Fin. Free Diving Fins have extra long blades to maximize movement through the water. They are popular among swimmers, advanced snorkellers, spear fisherman and with some scuba divers. Most prefer to wear them over bare feet, however in cold water conditions they can be used with soleless neoprene boots also called "socks".

Fin Sizing

Wearing Your Fins
Full Foot style fins slide on kind of like slippers. Some people may find it helpful to roll the heel of the fin down, slide the fin on, and then roll the heel back up once the foot is all the way in the fin pocket. All fins are designed to be most comfortable when the foot is in a swimming positing and may not feel as well when in a standing positing. Fins do not have a right and left.

Open Heel style fins have straps that require adjustment prior to using them. Once the fins are adjusted they can be easily taken off (and put back on) by pulling on the back of the strap. It is important to be careful with the adjustment buckles. While they are quite durable, pulling too hard or at a too severe of an angle can cause damage to the buckle.

To adjust an Open Heel fin (Power Fin) put on the boots, slide your foot into the fin and pull the strap over your heel. It is best to point your toe which will simulate the proper angle during in-water use. Firmly, but not forcefully pull the adjustment tabs straight back towards you. Adjust the fins equally on both the left and right side keeping the back of the strap centred. The amount of excess strap extending from the buckles should be about even on each side. Some older style fins have metal buckles that lock into place and cannot be adjusted while the fin is on your foot.

Too tight of an adjustment will make the fin quite difficult to take off and may cause your foot to cramp while kicking. Too loose of an adjustment will allow the fin to fall off, chafe your foot, or function inefficiently.

Fin Care And Maintenance
Fins like most scuba and snorkelling equipment should be rinsed in fresh water after each use, allowed to completely dry and stored in a cool dry place away from direct sunlight. Do not store your fins on their tips. Most fin materials have a memory and the blades will become distorted. Over exposure to sun causes fading, yellowing and discoloration. Fins should never be exposed to extreme heat (like inside of a car in the summer). High temperatures can cause the different materials in the blade and the foot pocket to separate and/or warp. Fins straps are one of the most commonly broken items. It is a good idea to have a spare strap to “Save-A-Dive”.