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Vamo Life

3.5" Side Bite Fins – FCS-1 Compatible (Set of 2)

$19.99
Shipping calculated at checkout.

FREE SHIPPING ON ORDERS $99+

Improve your board's tracking and stability with these 3.5" Side Bite Fins. Designed with the classic FCS-1 two-tab system, these fins are the perfect upgrade for stand-up paddleboards or surfboards that use a thruster or 2+1 fin configuration. Whether you’re dealing with the cross-chop at the Jupiter Inlet or just want a little more "bite" during your turns, these fins provide the extra grip you need.

Why You’ll Love Them:

  • FCS-1 Compatibility: The standard two-tab design ensures a secure fit in all traditional FCS-1 fin boxes.

  • Stable 3.5" Profile: Perfect depth for side bites—providing just enough hold to prevent side-slipping without creating unnecessary drag.

  • Durable Construction: Built to handle the everyday wear and tear of Florida coastal paddling.

  • Easy Installation: Uses standard FCS-style grub screws (not included) for quick setup or swapping.

Blueline Pro-Tip: If you feel like your SUP is "sliding out" when you make a turn or when you're paddling in windy conditions, adding these side bites is the single easiest performance upgrade you can make.

Product information

Ships directly from the brand. This item ships straight from our brand partner, and returns are handled through them.

Need a return or exchange? Email info@bluelinesurf.com or call 561-744-7474 with your order number, and we'll take care of it with the brand. Please don't ship returns to our Jupiter shop.

Return eligibility follows the brand's policy, and we'll confirm the details when you reach out. Sale items and gift cards are final sale.

The Easy Fix for a Board That Slides Out

These 3.5-inch side bite fins add hold to a paddleboard or surfboard with FCS-1 side fin boxes. They're one of the most requested fins at our Jupiter shop, and one of the simplest upgrades you can make to a 2+1 setup.

What You Get

  • Two 3.5" side bite fins (one set).
  • FCS-1 compatible two-tab base.
  • Grub screws are not included.

Will They Fit My Board?

These fit traditional FCS-1 two-tab side fin boxes. Each FCS-1 side box has two small round plugs with a set screw in each.

If your board has a different fin system, or you're not sure what it has, send us a photo or bring it by the shop before you order.

Best For

  • Stand-up paddleboards with a center fin plus two side fins (2+1).
  • Surfboards with FCS-1 side boxes in a thruster or 2+1 setup.
  • Windy days and cross-chop near the Jupiter Inlet.
  • Replacing a lost or broken side fin.

Product Details

Brand
Vamo Life
Fin size
3.5"
Fin base
FCS-1 compatible, two-tab
Quantity
Set of 2
Screws
Standard FCS-style grub screws, not included

Why Side Bites Help

If your SUP feels like it's sliding out when you turn, or it's hard to track in the wind, side bites give the tail more grip. At 3.5", they add hold without a lot of extra drag.

Install Tips

  • Seat each fin fully in its side box.
  • Snug the grub screws with a fin key. Don't overtighten.
  • Rinse fins and boxes with fresh water after saltwater sessions.

Need screws, a fin key, or a center fin? Call or message us before you order and we'll help you get the full setup.

Frequently Asked Questions

Are screws included?

No. These use standard FCS-style grub screws, which are sold separately.

Will these fit FCS II or Futures boxes?

These are made for FCS-1 two-tab boxes. If your board has FCS II, Futures, or another system, reach out and we'll help you find the right fins.

Can I use them on a surfboard?

Yes, as long as the board has FCS-1 side fin boxes.

Is this one fin or two?

Two. This listing is a set of 2 side bite fins.

How do these ship?

These ship directly from Vamo Life, so they aren't available for in-store pickup. Questions about fit before you order? Call or message us and we'll help.

Paddle surfer trimming down the line of a clean teal wave in Jupiter, Florida. Photo: Greg Panas

Paddle Surfing in Jupiter

More Hold When It Counts

On a steep face or a windy day, side bites help your board hold its line so you can keep trimming instead of sliding out. Pair them with the right center fin and your 2+1 setup is dialed.

Shop All Fins

Complete Your SUP Fin Setup

Pair your side bites with a Vamo Life center fin, or grab spare tool-free screws for the center box.