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FCS fins are fins that function as part of a Fin Control System.  The system was first designed by an Australian surfer, Brian Whitty, in 1995. 

The system allows a surfer to easily install and remove fins on a surfboard, creating more opportunity for versatility and making it easier to travel with a board.

The FCS fin system is the most widely used fin system in the world.  In this article, we’ll offer an overview of the three FCS fin types, as well as the characteristics and measurements that make each useful to a surfer. 

And if you’re looking for the best FCS for small waves, check out our product reviews for some of the best options for mounting smaller waves.

FCS fin categorization

FCS fins are classified by three main characteristics: base, depth, and sweep

Each of these characteristics alter surfboard performance, and the right combination of characteristics can improve specialty surfing skills.


The base of a surfboard is the length between the leading edge and the trailing edge where the fin meets the board.  

A longer base enhances drive and acceleration of a board.  The longer base functions to create a trajectory in the water that propels the board forward with more force.

Fins with a shorter base are best for maneuverability. 

They don’t lend much help in the control department, they lack grip or hold, but they do allow for tighter turns.


Depth is the length of fin that penetrates the water.  

This length is directly related to hold or grip, words used to describe the way a board functions in turns. 

Taller fins grip the water and improve a surfer’s control through turns.

Tall fins are more forgiving of inexperienced surfers. 

Shorter fins are best for trick maneuvers such as spins.

Shorter fins don’t offer much grip or hold, but they are better for speed and freedom.


Sweep is sometimes referred to as rake, an angle measurement that gauges the backward curve of a fin. 

Sweep is directly related to pivot, or the board’s ability to maneuver tight turns.  

A large sweep with a small offset is great for achieving a tighter turning radius. 

This kind of fin is often considered playful – and maybe a bit less predictable. the longer your turning arc will be.  Fins with less sweep are better for achieving tighter turns.

A small sweep, paired with a larger offset, helps propel a board forward. 

This type of fin promotes stability and create a more predictable ride. This fin type isn’t great for sharp, fast turns though.


 The shape of the fin’s face, which is thinnest near the topo and thickest at the base where the fin meets the board, is called foil. 

Foil affects the way water flows over the fin’s surface and greatly affects the way a board performs in the water, impacting both speed and maneuverability.  

The inside fin or fins almost always feature a symmetrical, convex shape on each side to improve stability. 

Outside fins can be customized to alter performance to a greater degree. A flat inside face n the outer fins balances control with speed and playfulness. 

A curved inside face is best for generating speed and fluidity in the water for – especially for fast, straight shot surfing.

Common surfboard fin setups

The most common surfboard fin setups include Single, Twin, Thruster, and Quad fin configurations. 

For longboards and traditional surfboards, the most common configuration is the single fin box. 

A single fin is best surfing fast, straight aways.  Single fins enhance stability and control in the water, increasing your board’s hold. 

On a longboard, the fin box is longer than what you would most likely find on a traditional surfboard. 

The longer fin box design allows a longboarder to move the fin forward for a looser feel and back when more control is needed.

Twin fins are a common configuration on shortboards.  This configuration affords a sense of greater freedom.

The dual-fin configuration gies a shortboard a skateboard-like feel, enhancing maneuverability and allowing a lot of play. 

Twin fins are also useful for increasing speed with a shortboard and for drawing out turns. Twin fins are the best for big waves.

The Tri-fin setup is one of the most versatile and popular fin configurations among modern surfers. It offers greater traction.

The center fin sits closest to the board’s tail, while the two outer fins are forward and angled towards the board’s center in pigeon-toe fashion.  

Also known as a thruster configuration, this configuration works for surfboards in nearly any shape or size to improve stability, maneuverability, and control. 

Plus, the configuration can be modified to allow you to run single or twin fin when the situation calls for it.

Quad fin systems feature four fin boxes and are the bet for speed.

In smaller surf, this system is a useful tool for generating speed. 

This configuration channels water to the end of your board and out the tail to create acceleration and enhance your speed. 

This also helps generate more drive to get through turns.

Quad fins can be useful in big-wave surfing to improve stability and hold.  The outer fins are positioned near the rails to promote greater stability.

Five fin configurations are meant to provide a surfer with greater variety in fin configuration choices, but all five fin boxes are not meant to be used at once. 

This configuration allows the greatest versatility. You can mix and match fins to match the surf conditions, or to better match your skill set and experience.

Upgrades to the original FCS system

In 2013, a new and improved FCS system hit the market.  These new fins, FCS II, lock into plugs on a surfboard without any screws or tools. 

The fin attaches with a more seamless connection so that the base of the fin sits flush with the board. 

The new system is also backwards compatible, allowing a surfer to use original FCS system fins with the new FCS II system with grub screws and a silicon insert to attach the original pieces.

Best FCS Fins for Small Waves

There are many factors to consider when selecting a fin configuration, including wave type. 

This chart is useful for making fin selections based on a variety of different water conditions. 

For small waves, single and twin FCS fins are best.

Remember, you should always consult an industry professional before using any new product to ensure it is safe and appropriate for your use.

The following FCS fin options may prove a good place from which to begin your search.

FCS II Reactor PC Carbon Tri Set

For small, hollow waves, the FCS II Reactor is a great option..

In hollow waves and beach breaks, the Reactor produces quick turns.  You’ll be able to get vertical with less effort, and you’ll be able to execute turns quicker and with less time in between.

The FCS II Reactor PC Carbon Tri Set is an upright fin with a low sweep angle that allows for tighter turns and more precise direction changes, a function of the smaller center fin. 

In addition to enhancing tight turns, the upright fin design minimized drag.

This design has made the Reactor one of the fastest fins on the market.

View at Amazon to learn more about how this product might work for you.


  • Great for performing aerial maneuvers
  • Fast fin reaction creates tight turn radius
  • Minimizes drag to improve speed


  • Medium-sized fins are great for generating moderate speed, but really low surf days may require large Reactor fins to generate maximum speed to get up.

FCS II MF Neo Carbon Black/Grey Large Tri Fins – Mick Fanning’s signature FCS II MF fin in Neo Carbon material for fast power surfing.

The FCS II Mick Fanning fins are a tri-fin configuration made with premium construction. 

Neo Carbon is a new material on the surfboard market, offering the best stiffness-to-weight ratio to provide extreme responsiveness in a lightweight fin. 

Precision molding optimizes flex – fins are stiff enough to load power without overloading or overpowering the flex in the tip.  

These fins are great for generating speed on small waves.  They help a surfer accelerate from one turn to the next quickly, creating a ‘whipping effect.’ 

This fin design is popular among both recreational and professional surfers.

It is a great option for open-face carving or executing drawn-out turns.

View at Amazon for more information on how this fin could work for your needs.


  • Flex through the tip of this fin creates a whipping effecting for more power and speed
  • Provides enhanced drive for low energy surf conditions


  • This fin setup works best for performance shortboards, especially those with moderate-to-extreme rocker.

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