Fins greatly affect the performance of a surfboard, especially shortboards, fish or hybrids, and especially for experienced surfers performing powerful bottom turns and snaps.
Fins are the extension of your surfboard, and will affect it in three main aspects:

The Pivot:
this is the ability of the fins to make short turns. Fins with little Pivot will make your surfboard doing short turns, which is what we need for small or relatively slow waves.
At the opposite, fins with lot of Pivot will allow you to make large bottom turns, which is perfect for fast and long waves.
The angle between the leading edge of the fin and the board, called "Sweep", is the parameter that influences the pivot capacity of your fins. The more angles, the more pivot your fins will generate.
The Hold:
fins with lot of hold will ensure a good grip, while fins with little hold will allow the surfer to easily slide the tail of his board.
To pick up your surfboard´s fins, you should consider the following:


1. The fin system of your surfboard.
There are various fin system, so, obviously, you must choose fins that are compatible with the fin system of your surfboard. The most popular is the FCS X2 plug system, which is used in 70% of surfboards.
It was the first removable fins system, a revolution in its time. It has been copied; you can now find brands offering almost the same plugs, like Eurofin which is the most popular, and therefore compatible with FCS fins.
Futures Fins plug system can represent the other 25% of the market. It´s a one screw removable fin system, stronger than the regular FCS X2 system, as the base of the fin is wider.
The rest of the market is shared by exotic systems such as FCS Fusion plug or fixed fins. Nevertheless, the brand new system developed by FCS, called FCSII, could change things, as you can mount and remove your fins without any tools.
2. Your weight
It´s essential to choose fins according to your weight. All the brands classify their fins by size, and each size fit to a weight range.
For small waves, it´s better to have smaller fins which enhance the maneuverability of you board, and in big waves it´s better to use bigger fins that will enhance the drive, grip and speed of your surfboard.
3. The size and speed of the waves that you are going to surf
Are you going to surf small punchy beachbreak waves? Choose straight fins, with little sweep angle, with a concave on the inner side of the lateral fins, to improve the stability and maneuverability of your surfboard and to make tight turns.
Are you going to surf fast and long waves, point break style? Choose fins with more sweep angle, to improve the drive and speed of your board, go faster and make large bottom turn.
Want one set of fins for everything? Choose versatile and balanced fins.
4. The power of the waves that you are going to surf and your surfing skills
The construction of the fins and the materials used will affect the rigidity of the fins.
Hard fins are ideal for powerful surfers or intermediate surfers, because they are more stable. The use of carbon and glass fiber contributes to increase the rigidity of the fins.
Fins with more flex are more dynamic; they help you to accelerate after a bottom turn. The quality of the materials used will make the fins going back to its original shape after flexing, giving to the surfer a feeling of reactivity, and helping to generate speed.
Honeycomb, fiberglass and carbon fiber are a must, they contribute to have flex and reactivity, combined with an extremely lightweight.
Not clear enough? Take a look at this video:
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Sebas
Sebas is the passionate creator and founder of Mundo-Surf, a space dedicated to those who live and breathe surfing. With a deep connection to the ocean and an overflowing passion for every wave, Sebas has turned his love for surfing into a mission: to share, inspire, and educate the community.
In addition to being an avid surfer, Sebas is an expert in surfboard manufacturing, an art that combines technique and creativity. Through his blog, he not only offers guides, reviews, and advice but also shares his experience in surfboard creation, helping others understand the process behind each design and material. At Mundo-Surf, Sebas invites us all to discover surfing at its fullest, from the right equipment to the personalized creation of surfboards.