FCS Fin Care & Compatibility Guide
Everything you need to identify, install, and maintain FCS fins.
FCS Fin Care & Compatibility Guide
Everything you need to identify, install, and maintain FCS fins.
Your FCS Fins
Scanned the QR code on your fin's packaging? You're in the right place. This guide covers how to identify your FCS (Fin Control System) setup, how to install and remove it correctly, and how to keep it in good shape for as many sessions as possible.
FCS is one of the most common fin systems on modern shortboards. Two versions are in circulation: the original dual-tab FCS ("FCS I"), which uses two teardrop-shaped plugs, and FCS II, a tool-free single-tab system with a deeper connection.
How to identify it: flip your board over and look at the tail. Two shorter oval plug slots per fin = classic dual-tab FCS. One longer, deeper slot with a textured base = FCS II.
Installing & Removing FCS Fins
Dual-tab (FCS I): Insert both tabs into the plug slots and press down evenly until fully seated. Use the fin key to lock the rear plug in place. To remove, insert the key into the rear plug, twist to compress it, and lift the fin out.
FCS II: No tools needed. Angle the fin slightly and press down until it clicks fully home. To remove, pull up on the fin's built-in tab.
Care & Maintenance
- Rinse fins and fin boxes with fresh water after every session, especially in saltwater.
- Dry away from direct sun or heat — prolonged UV and heat exposure can warp or discolor the fin and the box plugs.
- Clear sand or grit from the plug slots before inserting a fin so it seats fully.
- Store fins flat or in a fin bag/sock to protect the leading edges from chipping.
- After any hard impact (rocks, reef, riverbed), check the base of the fin for hairline cracks before your next session.
- Keep a spare fin key and a couple of spare grub screws (FCS+ fins) in your kit.
Compatibility
FCS and FCS II fins only fit boards molded with the matching FCS plug boxes — the two generations are not interchangeable with each other, and neither fits Futures or US Box boards without a box conversion.
Not sure which template or size is right for your board and riding style? Try our Surfboard Fin Guide.
FAQ
Still unsure? Reach out and we'll help you identify your setup.
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Look at the tail underside: two shorter oval plug slots per fin means classic dual-tab FCS; one longer, deeper slot with a textured base means FCS II.
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No — FCS II is tool-free. Press-fit the fin in and pull the built-in tab to release it; a fin key isn't needed and won't fit.
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Clear any sand or debris from the plug, confirm the fin is fully seated, and check the tab and plug for wear. A worn plug may need replacing.
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Inspect after every hard impact. Replace when you see cracking at the base, a rounded or worn tab, or noticeably reduced hold in the box.
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No. The tab depth and shape differ between generations — always match your fin to your board's specific box.
Replacement FCS Fins
Shop replacement fins for your FCS setup.
