Choosing fins for surfboards is less about picking a universal winner and more about matching the set to the board's system and intended feel. The FCS II Reactor and Captain Fin Jeff McCallum Keel are close in price, yet their designs point to different uses. Before weighing construction or cost, identify the fin system and the kind of response you want from the board.
Quick verdict
With a $2.47 gap, setup should lead the choice. FCS II Reactor Neo Glass Medium is the match when the board takes FCS II and a three-fin arrangement. Captain Fin Jeff McCallum Keel Acid Splash is the match for a Futures fin setup built around a keel profile. Both are new fin sets, but they are aimed at different surfboard configurations.
Compact comparison
| Product | Listed price | Configuration | Design cue |
|---|---|---|---|
| FCS II Reactor Neo Glass Medium | USD 89.48 | 3-fin set; FCS II | Upright template |
| Captain Fin Jeff McCallum Keel Acid Splash | USD 91.95 | 2-fin set; Futures Fins | Fiberglass; elongated profile |
Where each product wins
- FCS II Reactor Neo Glass Medium: It wins for quick turns, sharp direction changes, and the convenience of tool-free installation. Those details make its purpose especially clear for responsive surfing in beach breaks and tight pockets.
- Captain Fin Jeff McCallum Keel Acid Splash: It wins for a retro twin fin fish and the smooth, down-the-line approach described for its elongated keel shape, sweep, and wider base.
Product notes
FCS II Reactor Neo Glass Medium
FCS II Reactor Neo Glass Medium is the more focused choice for an adult surfer who wants an upright template and quick, sharp direction changes. Its design is connected with fast, responsive surfing in beach breaks and tight pockets, while the tool-free installation is useful when convenience matters. The limitation is the stated medium size and recommended 65-80 kg / 145-175 lb range; the fit decision is tied to those rider parameters. The charcoal / black finish is also clearly defined for shoppers who want that color. Choose this set when the upright, responsive brief is the priority and the rider's weight aligns with the specified range. Its role is specific rather than interchangeable with the keel-style set.
Captain Fin Jeff McCallum Keel Acid Splash
Captain Fin Jeff McCallum Keel Acid Splash has a specific design brief. The elongated profile, sweep, and wider base are described for smooth down-the-line speed and control, giving a concrete reason to choose it for that style of surfing. Fiberglass construction and the Acid Splash finish add clear design detail without changing the main decision. Its limitation is the stated stiff flex, which will not suit a shopper specifically seeking a different flex character. The two-fin format also narrows the use case for anyone who needs a three-fin replacement. Choose this set when the board's shape cues align with a keel-oriented setup and the intended ride calls for its defined profile and flex.
Final choice by use case
- Choose FCS II Reactor Neo Glass Medium when your surfboard takes FCS II, you want the upright-template turning brief, and the adult 65-80 kg / 145-175 lb range fits the rider. Its USD 89.48 price is the lower of the two, but the setup match matters more than the small gap.
- Choose Captain Fin Jeff McCallum Keel Acid Splash when you have a retro twin fin fish with Futures Fins and want the described down-the-line approach. At USD 91.95, it costs $2.47 more, so choose it for the keel design rather than for a small price difference.
