Quad fin setups gained real traction in the early 2000s. They promise better speed and glide while aiming to match a thruster’s maneuverability. In practice you often trade one attribute for another. A quad will not match a twin fin’s pure glide, and if you match thruster-style turning, you usually sacrifice some drive. Still, when dialed in properly, quads can deliver a lively blend of speed, hold, and looseness.

Understanding Rear Fin Placement

The lateral position of your rear fins determines the ideal foil and overall feel.

  • Railside placement: As the fin moves toward the rail, a flat inside foil gives more hold and drive. Most common on wider tailed, grovel shapes.
  • Midway placement (eg. Rusty): Fins set between rail and stringer perform best with a double foil, typically an 80/20 distribution. Most common on daily driver style boards.
  • Center/Stringer placement (eg. McKee): When the fin sits close to the stringer, a symmetrical 50/50 foil loosens the tail and makes turning easier. Most common on pin tail surfboards.

Foil Choices and Their Effects

Each foil profile changes how the board tracks, pivots, and accelerates.

  • Flat inside foil: Maximizes drive in small surf. It locks the tail in when you push off the rail.
  • 80/20 double foil: Common on many Futures quad rear fins. Offers some of the drive of a flat inside foil with some of the looseness of the 50/50 foil.
  • 50/50 symmetrical foil: Offers the least hold/drive and the easiest rail to rail experience.

Practical Recommendations

When choosing quad rears for a Futures-box board, consider these sets:

  • Controller split keel (bamboo set): Ideal for wider tailed grovel boards with rear fin placement near the rails and clustered with the main side fins.
  • Stretch quad: Works well if the rear fins sit closer to the stringer or if the board is too tracky.
  • F8 or F6 quad set: Reliable all-around option. For larger tailed boards or heavier surfers, chooose the F8s otherwise, go with the F6s. For quads, I recommend sizing down vs. going with larger fins for your weight.

Check Manufacturer Recommendations

If you are buying a new board from a major brand, consult Futures’ online fin finder. Find your board model by manufacturer and board name to see their suggested fin sets. If your board isn’t listed, consider reaching out to the shaper to get their recommendation for proper fins. Prior to buying, I’d check to see if your current sets of fins are a similar template/surface area to whatever is suggested. New fins are pricy.

Conclusion

Selecting quad rears boils down to fin placement, foil choice, and rider style. Match rail placement with flatter inside foils, move toward 80/20 or 50/50 profiles as fins shift inward, and adjust size for weight and tail width. Finally, lean on manufacturer guides to confirm your pick.