How to pick a pair of freediving bi-fins – A buying guide

Ok, you need a pair of long blade freediving fins. You know that much. But how do you move on from here? How do you chose the perfect pair? This guide is a good place to start.

Sometimes people ask me what are the best freediving fins? Well, that’s an impossible question to give a straight answer to. What is perfect for me might be ok for you and really bad for someone else. When choosing a pair of freediving fins there are a few things you need to consider.

  1. Type
  2. Fit
  3. Use & Performance
  4. Blade Material & Softness
  5. Price

There are two main types of long blade freediving fins:

  • Integrated blade and pocket
  • Separate blade and pocket

Fins with integrated blade and pocket are moulded in one piece and typically made out of some type of thermoplastic material. This is typically a low cost fin. But they can still be very good, for some people even the best possible choice considering Fit, Use, Performance and Price.

Cressi Gara 3000 LD

My favorite integrated fin is Cressi Gara 3000 LD, where LD is for Long Distance and indicates a softer blade. This is a durable fin with great performance for a plastic fin and a comfortable foot pocket that fits a lot of feet. I have done comfortable 40m dives with them but I know people that have done 50 and 60m CWT dives with them as well. They usually cost from 70 – 100 EUR.

I do not recommend the cheaper Cressi Gara 2000 HF as they are too stiff for almost any thinkable person and use.

Fins with separate blade and foot pocket

Fins with separate blade and pocket are sometimes possible to disassemble and reassemble with screws connecting blade with pocket and sometimes they are assembled with pocket and blade glued together. No matter what method is used the important aspect here is they allow you to match the perfect pocket with the perfect blade for you. So let’s move on to fit.

You need a fin that fits your foot. If it doesn’t fit well it won’t be good for you. The best approach is to try as many pockets as you can. When I was looking for new fins I used to ask anyone I met with similar size to me to try their fins to get a feel of various foot pockets. Everybody without exception was happy to let me try their fins. I do not recommend anyone to buy a pair of fins online without trying them on first, ideally in the water under normal use. If that’s not possible at least on dry land. Remember to try on with the same type of socks you intend to use if you are planning on using socks. Neoprene socks can help keep your feet warm, fine tune a fit and protect the skin on your feet from blisters and bruises.

Use & Performance
How are you going to use your fins? In cold or warm water? For shallow recreational diving? For deep performance diving? for long dynamic swims? Fighting big fish while spearfishing?

The first question is very important already when you consider fit as the water temperature determines if you will need a neoprene sock to keep your feet warm and how thick that sock needs to be. A fit with a 3mm sock allows you to dive comfortably in anything from tropical waters to 15-16 degrees Celsius, while spear fishers in Norway may use as thick as 9mm socks to stay warm in the freezing cold sea.

The more performance oriented diving you intend to do the more you have to consider blade material and stiffness.

Blade Material & Stiffness
There are basically 3 main type of blade materials.

Plastic – cheap and can take a beating. Material fatigues by time and sun exposure. Can over bend and deform.

Fiber Glass – performance closer to carbon with a price tag closer to plastic. Durable. Material fatigues slowly and only after long term use.

Carbon – top performance with a high price tag. Sensitive to external impact and needs to be carefully packed to survive travel. Scratches and dents may weaken the blade.

Plastic blades tend to stiffen up in very cold waters while fiberglass and carbon doesn’t.

So how do these materials affect performance? Basically the higher performance of the blade, the more of the energy you invest in your kick to bend the blade, the more of that energy you get back in the form of propulsion as the blade returns to it’s original straight position throughout the kicking cycle. Carbon pays you back the most while plastic the least.

If you don’t want to spend big money, do not care too much about equipment care and maintenance and are planning on diving in shallow to medium depths of 5 – 30m, plastic is for you.

If you have a little bit of money to spend, want to dive a little deeper and want to enjoy a more comfortable finning experience, fiber glass is for you. The price is closer to plastic while performance is closer to carbon.

If you have the money to spend, want the best performance and do not mind being a little more careful with your equipment, carbon is for you.

When you have made your choice of material you need to consider the stiffness of the blade. Plastic fins may come in two levels of stiffness at best, while fiberglass and carbon blades tends to be offered in 3-5 stiffness levels. Unfortunately there is no industry standard and manufacturers may use various ways to indicate stiffness of their blades, but usually it can be translated into something like this; Soft, Medium-Soft, Medium, Medium-Hard, Hard.

For almost any person and use the softer side of that span is the way to go. Very few divers need to go beyond a medium blade in stiffness while most would be good with a soft or medium-soft. A softer blade allows for a relaxed and efficient finning technique over greater distance with less energy input. A spearfisherman that dives in strong currents and fights big fish might want to consider a slightly harder blade to get the extra thrust a stiffer blade offers while needed, but keep in mind that the stiffer blade might affect the finning technique and cause earlier fatigue of the legs and ankles when not needed.

Foot pocket with long rails

To complicate things further, the design of the foot pocket actually affects the stiffness of the blade as well. Most foot pockets have rails that run along each side of the blade. The stiffer the rail the less the blade will bend in the section of the blade positioned between the rails. A shorter and or a softer rail will allow the blade to bend easier closer to the foot pocket. Some of the most popular foot pockets are Omer Stingray, Mares Razor and Pathos Fireblade where the Stingray’s rails are harder and the Razor and Fireblade’s softer.

For most of us price is a big issue and at the end of the day one of the strongest considerations when choosing a pair of fins. Plastic fins tend to range from 50 to 120 EUR, Fiberglass 150 to 300 EUR and carbon from 300 to 500 EUR. But there are exceptions, For example a pair of Allemani fiberglass fins cost around 400 EUR and their supporters swear by their performance. You may on the other hand be able to get a complete pair of fins with carbon blades from for example Carbon Tec or Leader Fins for as little as 200-250 EUR. At the end of the day, you get what you pay for.

So what am I using? For the last year I’ve been using Captain Nemo Powerfin fiber glass blades from Waterway with stiffness 2 out of 5, medium-soft. 85.50 EUR directly from Waterway. I started with factory assembled Captain Nemo Lite pockets with very short rails. I dived to 60m CWT with these fins. By time though I found that the blade bent a little more and closer to the pockets than I wanted, and finally swapped them for a pair of Mares Razor pockets with more conventional, albeit soft rails. Now the blades behave much more like I want them and I’m very happy with the performance.

A few final words. No matter your choices, try as many fins as you can before you buy so that you get a clear idea of what you are looking for. Don’t buy blindly online, support your local retailer if there is one available or at least make sure you have tried the fins you are ordering online beforehand to avoid costly mistakes.
Last but not least. Listen to advice but don’t take other people’s personal preferences as facts. What’s perfect for me might not work at all for you.