Surfboard Fins

Surfboard fins from Deflow for shortboards, fish, mid-lengths and longboards. The collection covers thruster and quad sets, twin, twin keel and twinzer fins, a twin fin set with a centre fin, side bites, fins for asymmetrical boards, and single fins for longboards in fibreglass, honeycomb, carbon and foam core constructions.

Choosing a fin setup

• Thruster (three fins): the most common shortboard setup, giving a balance of drive, hold and control in a wide range of waves.
• Quad (four fins): extra speed and hold down the line, popular in clean, hollow waves and on fish and groveller shapes.
• Twin fins and twin keels: loose and fast, made for retro fish and twin fin boards. Keel fins are long and low with a wide base.
• Twinzer: a twin fin setup with a small extra fin in front of each main fin.
• Twin plus one and single fin with side bites: a centre fin with two smaller side fins, often used on mid-lengths and longboards.
• Single fins: the classic longboard and mid-length setup, with sizes here from 6.5 to 10.5 inches. Larger fins add hold and stability for noseriding and trim, while shorter fins feel looser.
• Asymmetrical fins: made for asymmetrical boards and offered in goofy and regular versions.

Fin box compatibility

Before you buy, check which fin box system your board uses. Common systems include FCS, FCS II, Futures and the US box used for longboard single fins, and they are not interchangeable. Many Deflow fins are offered with a choice of base, such as single tab or twin tab, so select the option that matches your boxes. If you are unsure, look at the fins your board came with or the board maker's details, and check each product page for the bases on offer.

Flex, template and size

• Flex: stiffer fins give drive and hold in stronger surf, while more flexible fins feel lively and release more easily in smaller waves. Where a fin's flex is stated, it is on the product page.
• Template: an upright fin with little rake pivots for tighter turns, while a raked fin that sweeps back gives longer, drawn-out turns.
• Construction: fins here are made in fibreglass, honeycomb core, carbon and polyurethane foam core, each with a different feel and weight.
• Size: many sets come in sizes such as S, M and L, which are generally matched to surfer weight. Check the size guide on each product page.

Care and safety

Fin edges can be sharp, so handle them with care and keep them away from children. Rinse fins in fresh water after surfing, check the screws or fixings are secure before each session, and take fins out of the board for travel or storage to avoid damage to the boxes.

Common questions

Which fins fit my surfboard?

The fins must match your board's fin box system. Check your boxes or existing fins, then choose the matching base option on the product page.

What size fins do I need?

Fin set sizes are usually based on body weight, with heavier surfers suited to larger fins. Check the size guide on each product page and choose the size that matches your weight.

What is the difference between thruster and quad fins?

A thruster has three fins and suits most shortboards and conditions. A quad has four fins, with no centre fin, and gives extra speed and hold, especially in clean, steeper waves.

What size fin should I use on a longboard?

Larger single fins, around 9 to 10.5 inches, give stability and hold for trim and noseriding. Smaller single fins feel looser and suit mid-lengths and 2+1 setups.

Add a leash and traction pad, see our wetsuits or visit the surf shop.