True Ames True Ames Greenough 4A Single Fin
True Ames True Ames Greenough 4A Single Fin
True Ames True Ames Greenough 4A Single Fin
True Ames True Ames Greenough 4A Single Fin
True Ames True Ames Greenough 4A Single Fin
True Ames True Ames Greenough 4A Single Fin
True Ames True Ames Greenough 4A Single Fin
True Ames True Ames Greenough 4A Single Fin
True Ames True Ames Greenough 4A Single Fin
True Ames True Ames Greenough 4A Single Fin
True Ames True Ames Greenough 4A Single Fin
True Ames True Ames Greenough 4A Single Fin
True Ames Greenough 4A Single Fin
True Ames Greenough 4A Fin specs diagram - versatile medium profile fin
True Ames True Ames Greenough 4A Single Fin
True Ames True Ames Greenough 4A Single Fin
True Ames True Ames Greenough 4A Single Fin
True Ames True Ames Greenough 4A Single Fin
True Ames True Ames Greenough 4A Single Fin
True Ames True Ames Greenough 4A Single Fin
True Ames True Ames Greenough 4A Single Fin
True Ames True Ames Greenough 4A Single Fin
True Ames True Ames Greenough 4A Single Fin
True Ames True Ames Greenough 4A Single Fin
True Ames True Ames Greenough 4A Single Fin
True Ames True Ames Greenough 4A Single Fin
True Ames Greenough 4A Single Fin
True Ames Greenough 4A Fin specs diagram - versatile medium profile fin
Greenough 4A fin specs diagram
★ 5.0 (8 reviews)

True Ames Greenough 4A Single Fin

IN STOCK NOW

By True Ames
From $74.00 USD
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The Greenough 4-A Single Fin is the most iconic, functional and versatile single fin you can buy. That's because it works extremely well on just about every type of surfboard. The 4-A has been around for over 40 years, and it is still the most popular single fin design due to it's all around well-balanced performance. Check out our technical diagram of George Greenough's famous fin template for a more in depth look at the design characteristics.

Fin Construction: Solid Fiberglass
Designer Info

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Designer Name: George Hamilton Perkins Greenough
Designer Origin: Santa Barbara, California
Designer Bio: Greenough treated the fin as a true hydrodynamic foil—pursuing high-aspect, lower-drag outlines and intentional flex to reduce drag and increase control through powerful arcs. His "high aspect ratio" and signature flex-fin concepts helped unlock faster, more radical surfing lines and were central influences on the 1960s–70s performance/shortboard progression.

🚚 📦 Ships from our San Francisco shop
🔄 Easy returns within 30 days
🏪 Visit us in person: 4051 Judah St

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