FDX1 Tri-Quad Fins

FDX1 Tri-Quad Fin Set — 5 Fins

The FDX1 Tri-Quad is a five-fin set that covers two complete configurations in a single package. Run it as a quad using the four side fins, or as a thruster using the center fin and the two front side fins. Both setups use the same FDX1 template: a neutral, balanced geometry designed by Flying Diamonds to serve as a performance baseline across your quiver.

Key Features

• Five-fin set — one purchase covers both a full thruster and a full quad configuration, no additional fins needed
• Neutral, balanced FDX1 template — not overly upright or raked, built to function as a quiver-wide performance reference point
• AirFlex construction — polyurethane foam air core with high-strength fiberglass and epoxy resin shell, delivering the lightest possible weight with optimal rebound under load
• Balances speed, flow, and response in both thruster and quad configurations — Flying Diamonds' stated performance priorities
• Available in Medium (Black Multi-Tone) and Large (Gray Multi-Tone); compatible with FCS II (Dual Tab 2) and Futures

Two Setups, One Package

Thruster Setup
Center fin + two front side fins — the same three-fin combination as the FDX1 Tri Fin Set. Standard thruster performance: balanced drive, pivot, and control.

Quad Setup
All four side fins, no center fin. The rear quad side fins are included exclusively in this five-fin set — they are not part of the Thruster set. Switching between setups requires no additional purchases; everything you need is in the box.

AirFlex Construction

AirFlex starts with a precision-shaped polyurethane foam core — an air-core interior that removes excess weight while holding the fin's shape and structural integrity. This core is wrapped in high-strength fiberglass and laminated with epoxy resin, producing a durable outer shell.

According to Flying Diamonds, this build delivers a balanced, predictable flex pattern with quick response and smooth feedback under load. The fins feel lively and responsive through turns, while remaining stable and controlled when conditions demand it. The construction is designed to perform consistently across a wide range of conditions with every board you ride.

Fin Specifications

All measurements as published by Flying Diamonds of California. *Rear Quad Side fins are exclusive to this five-fin set.

Compatibility

Fin Box System

• FCS II (Dual Tab 2) — Medium (Black Multi-Tone) and Large (Gray Multi-Tone)
• Futures — Medium and Large; confirm current stock at time of purchase

Board Type

• Shortboards and mid-lengths with five-fin boxes — allows switching between thruster and quad on the same board
• Works across separate boards: thruster on one, quad on another — same fins, same construction throughout

This Fin Set Is Right for You If…

• You ride a five-fin board and want the flexibility to switch between thruster and quad setups without buying two separate sets of fins
• You want to experiment with both configurations using identical construction — so any performance difference you feel comes from the setup, not the fins
• You prefer a neutral, all-around template over a specialist fin built for a specific wave type
• You ride FCS II or Futures boxes and want a single versatile set that covers both configurations

Why the FDX1 Tri-Quad

• Two complete fin setups in one purchase — thruster and quad, same template, same construction, no compromises
• AirFlex construction is consistent across all five fins — the flex and rebound characteristics are identical whether you run three or four
• Neutral FDX1 template works as a quiver anchor: a reliable performance baseline across different boards and conditions
• Available in FCS II and Futures — the two most common fin box standards in shortboards and mid-lengths