Matt Biolos Split Keel Quad

These fins are specifically designed for hybrid and fish-style boards. They excel on boards with wider tails where you need extra hold and stability to prevent the tail from sliding out during turns.

The solid fiberglass construction provides a much stiffer, more responsive feel. Unlike molded plastic fins that can flex under pressure, these maintain their shape, giving you more drive and a predictable, locked-in sensation when you push hard through a turn.

These are designed for the FCS II fin system. They are compatible with all FCS II boxes, but they are not compatible with the older FCS dual-tab (FCS I) boxes unless you use specific adapter screws.

A quad setup generally offers more speed and hold, especially in down-the-line waves. By removing the center fin, you reduce drag, while the split keel design provides the necessary bite to keep you stable through high-speed maneuvers.

While they are high-performance fins, they are quite forgiving due to the stability they provide. However, they are primarily engineered for intermediate to advanced surfers who want to maximize the potential of a fish or hybrid shape.