Introduction
In the previous article we discussed about the wetsuit, necessary to keep ourselves warm and comfortable. In this article we will talk about fins, the piece of equipment that helps us move around more efficiently, thus enabling us to cover the same distance much faster.

Types of fins
There are many ways to categorize fins. Walking in a diving shop and asking for fins will most certainly raise the question “What kind of fins are you looking for?”. To make things simple we will start by discussing the parts of the fins.

The Shoe
The shoe of the fin is the part where the fin is attached to our foot (hence the name). We have basically two types of fin shoes, “open heel” and “closed heel” (see picture). Open heel shoes have a strap that keeps the fin in place. It does not provide the “firm” attachment a freediver needs. Wearing them and fining, will most certainly create a loss of energy, suitable for scuba divers because it fulfils their needs. They wear diving boots instead of socks (so they can walk fully equipped on rocks) and they just slip the open heel shoe on, close the strap and dive. We freedivers, on the other hand, do not have such heavy equipment and do not really need boots to walk on rocks. Bearing less, lighter equipment, we just wear our socks next to the water, put our closed heel shoes on and dive. This way we can take advantage of the better link between fin and foot that the closed heel shoe provides. So, if you are looking for a freediving fin, go for closed heel shoes. Now you know why. There are also fin shoes that are permanently attached to a blade and those where the blade is exchangeable. The choice is yours although using a stand-alone shoe gives you more choices to custom make a pair of your shoe-blade selection. Most stand-alone fin shoes can be attached to most stand-alone blades.

Fin length
The length of the blade is another way to categorize fins. “Short” and “Long” are the two options here, although the length is not always precisely the same within each category. Short blades are better for beginners, because the do not provide great resistance, thus allowing the diver to master the correct fining technique. Once the correct technique is mastered, the diver can move to a long blade. And then, the never-ending story of fin choice begins…

Blade material
Blades are made of several materials. First we only had one choice, plastic. These blades have one main advantage. They are cheap. So cheap in fact that the blade is sometimes many times cheaper than the fin shoe. So, if the blade breaks, it is easy and costless to replace (if it is detachable from the shoe). But this low price comes with a price: Plastic blades are not very efficient and are usually too stiff (more on this later). Another material we can choose is fiberglass. These fins are more expensive than their plastic counterparts but their advantage is that they are much more efficient. The same holds for carbon fiber fins. They are more efficient than fiberglass fins. Of course, nothing is free and the more efficient the material, the higher the price. So carbon fiber fins, being the most efficient are also the more expensive choice. There are of course blades that fall in the “sandwich” category, the cheap, wannabe carbon blade. These are mainly made of fiberglass but have some layers of carbon fiber on the top and bottom to make them look as if they are made of carbon fiber. Stay away from these as the two materials do not match very well and these blades are subject to delamination, a process that sometimes separates the two layers and destroys the blade by breaking it.