Greenough 4A Volan
The Greenough 4-A Single Fin is the most iconic, functional and versatile single fin available, because it works extremely well on just about every type of surfboard.
The Fin
The Greenough 4-A Single Fin is the most iconic, functional and versatile single fin available, because it works extremely well on just about every type of surfboard. The 4-A has been True Ames' bread and butter for over 40 years now, and it is still the most popular single fin design there is due to it's all-around and well-balanced performance. Our Volan fins are fine-tuned with precision foils as well as proper flex. The Volan panels are meticulously hand-laid and templated ensuring optimal weave orientation and superior strength, with flex coming more from the body rather than just the tip. This enhances speed and projection off the bottom and through turns, making our Volan fins a pinnacle of the highest performance flex characteristics.
Form | Medium profile, full base coupled with a tapering & moderately flexible tip
Function | A fin that will hold when you need it to and release when the time is right
Feel | Neutral-positive, perfectly-balanced, a fin that will drive off the bottom, and have an acute responsiveness through arcing turns
Overall | Versatile - designed for all board shapes and surf conditions
Specifications
Size-by-Size Measurements
Height, base, area, and weight for every 4A size. Specs confirmed across True Ames and Cleanline Surf.
| Size | Height | Base | Area | Weight |
|---|---|---|---|---|
| 6.5" | 6.49" | 5.42" | 22.86 sq in | 227g |
| 7.0" | 7.09" | 5.67" | 24.89 sq in | ~255g |
| 7.5" | 7.55" | 5.95" | 26.86 sq in | ~280g |
| 8.0" | 8.11" | 6.09" | 28.85 sq in | ~305g |
| 8.5" | 8.51" | 6.42" | 32.19 sq in | ~330g |
| 9.0" | 9.14" | 6.93" | 36.13 sq in | ~355g |
| 9.75" | 9.71" | 7.09" | 39.93 sq in | ~380g |
| 10.0" | 10.08" | 7.42" | 43.85 sq in | ~400g |
| 10.5" | 10.63" | 7.91" | 48.44 sq in | 425g |
Technical Details
Specs no other retailer publishes.
Moderate-to-heavy. More swept than a pivot fin (~28°), less than a hatchet (~40°).
Industry standard for all single fins — equal shape on both sides for balanced rail-to-rail performance.
Screw + plate. Does NOT fit Futures or FCS boxes. For 2+1 setups, buy the 2+1 Combo pack.
Raw, unpolished finish with natural amber tint. Flex comes from the entire body of the fin, not just the tip. Each fin has subtle hand-finished texture and character.
Inspired by bluefin tuna caudal fins. High-aspect-ratio design that launched the shortboard revolution.
Sizing Guide
Start with 1 inch of fin per foot of board, rounded up to the nearest available size. You can go up to 1" larger for heavier riders, narrower tails, or overhead waves. For 2+1 setups, drop 1.5–2" from your single-fin size — the side bites add hold, so the center fin can be smaller.
| Board Length | Single Fin | 2+1 Center |
|---|---|---|
| 5'6" – 6'0" | 6.5" | — |
| 6'0" – 6'6" | 6.5" – 7" | 6.5" |
| 6'6" – 7'0" | 7" – 7.5" | 6.5" – 7" |
| 7'0" – 7'6" | 7.5" – 8" | 7" – 7.5" |
| 7'6" – 8'0" | 8" – 8.5" | 7" – 7.5" |
| 8'0" – 8'6" | 8.5" – 9" | 7.5" – 8" |
| 8'6" – 9'0" | 9" – 9.75" | 7.5" – 8" |
| 9'0" – 9'6" | 9.75" – 10" | 8" – 8.5" |
| 9'6" – 10'0" | 10" – 10.5" | 8.5" – 9" |
| 10'0"+ | 10.5" | 9" |
Size up if you're over 200 lbs, riding a narrow-tailed board, or surfing overhead+ waves. Size down for wide tails, small gutless surf, or if you want a looser feel. For 2+1 setups: the larger your side bites, the smaller the center fin can be.
Why Volan
Volan is a woven fiberglass cloth — heavier, coarser, and more flexible than the solid fiberglass used in the standard 4A. It's laid by hand over the fin blank and finished with a resin that cures to a warm amber tint. No two volan fins look exactly the same.
The difference isn't cosmetic. Solid fiberglass flexes mostly at the tip — the body stays rigid, so energy transfers immediately. Volan flexes through the entire fin. It loads energy into turns and releases it progressively, giving a smoother, more connected feel. Surfers describe it as "warmer" — the fin does more of the work, trimming and holding without demanding constant input.
The extra weight is part of the design. A volan 4A is roughly 15–20% heavier than its solid fiberglass counterpart, and that mass adds momentum. Through flat sections and lulls, the fin carries speed instead of stalling. On a longboard trimming down the line, that momentum is the difference between making the section and bogging.
When to choose Volan
Volan's momentum and smooth flex match the trim-and-glide style of classic shapes. The fin carries you through sections instead of demanding constant pumping.
If you like a fin that loads into turns and releases gradually — more flow, less snap — volan rewards a patient, drawn-out style.
Down-the-line waves let volan's progressive flex and carry shine. You'll notice the difference most on long, open faces where trimming speed matters.
The amber tint, raw cloth texture, and hand-finished irregularity are part of the appeal. Volan fins look like they belong on a traditional board.
When to stick with solid fiberglass
If you're pumping, snapping, and surfing aggressively, solid fiberglass gives more immediate response and a stiffer drive through turns.
Short, steep waves reward the instant energy transfer of solid glass. Volan's progressive flex can feel sluggish when the wave demands quick changes.
Solid fiberglass is lighter. For boards where swing weight matters — shorter single fins, 2+1 setups on mid-lengths — solid glass keeps the tail light.
Volan vs Solid Fiberglass at a Glance
| Volan (this fin) | Solid Fiberglass | |
|---|---|---|
| Flex Pattern | Full-body, progressive | Tip-focused, immediate |
| Weight | Heavier (~15–20% more) | Lighter |
| Feel | Warm, smooth, forgiving | Direct, precise, snappy |
| Speed Through Flat | Carries momentum | Needs pumping |
| Turn Response | Gradual load and release | Instant engagement |
| Finish | Raw amber tint, hand-laid texture | Matte, uniform |
| Best Waves | Point breaks, mellow walls, long lines | Beach breaks, punchy hollow waves |
| Best Boards | Traditional logs, gliders, hulls | HP longboards, mid-lengths, 2+1 setups |
Both versions use the same 4A template — same outline, same rake, same foil. The difference is entirely in how the fin flexes and how that flex translates to feel underfoot.
Want the stiffer, lighter version?
Shop the Greenough 4A in solid fiberglass ›Greenough 4A Volan
The Greenough 4-A Single Fin is the most iconic, functional and versatile single fin available, because it works extremely well on just about every type of surfboard.