True Ames Greenough 4-A Single Fin Kelp

True Ames Greenough 4-A Single Surfboard Fin

The Greenough 4-A surfboard fin is not only the bread and butter of the True Ames collection, but it’s also been the most popular single fin worldwide for decades, and for good reason! Its incredible functionality and versatility means it’ll work on just about anything.

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The man behind this revolutionary fin is George Greenough, a surf innovator whose wave-riding performance transformed the sport since the '60s. Greenough’s innovations led surfing from traditional logging to progressive techniques, especially with his Velo-Spoon kneeboard designs in the '60s. 

He drew inspiration for his fin templates from studying tuna tail fins, the fastest and most agile fish in the ocean. The high-aspect ratio design he developed allowed surfers to place themselves in critical wave sections, enabling more radical turns. The Greenough 4-A surfboard fin is a well-balanced fin, combining a full base with a tapering, moderately flexible tip for drive.

It provides excellent drive off the bottom, responding sharply through turns, designed for both speed generation and pocket surfing. This fin holds when needed, offering control and release at the right moments for smooth, responsive high-performance surfing.

History lesson aside, the Greenough 4-A surfboard fin is a truly well-balanced fin. Its full base coupled with a tapering, moderately flexible tip provides a solid amount of drive off the bottom, and an acute responsiveness through arcing turns. Designed for both speed generation and spending time surfing in the pocket, the 4-A is a fin that will hold when you need it to and release when the time is right.

• A true all-rounder, the 4-A is one of the most versatile single fins ever designed 
• The larger sizes are great for single fin longboards, while the smaller and medium sizes pair well with mid-lengths, performance single fins, and 2+1’s
• Best of both worlds performance: solid base and width create stability and drive, while the rake and flexible tip enables top-to-bottom turns and manoeuverability
• Solid fiberglass construction, flat matte finish

Who are True Ames?

True Ames Surfboard Fins are renowned in the surfing world for their quality, design, and history. Founded in 1979, True Ames began by crafting fins to enhance performance. The company’s first fins were made for a small group of surfers in California. Over the years, True Ames expanded its reach, making fins for top athletes.

Their early designs were influenced by the growing interest in performance surfing during the 1970s. True Ames quickly became a leader in the fin-making industry. The fins' designs focused on improving speed, control, and turning ability. Each fin was handcrafted with meticulous attention to detail and functionality. As the sport evolved, True Ames fins adapted to new trends and technologies.

The brand has always been known for using high-quality materials in its fins. True Ames has also collaborated with legendary surfers to create custom fins. One of their iconic fins was the "Greenough" model, inspired by George Greenough's surfboard designs. The company’s innovations helped shape the modern surfboard fin as we know it today. True Ames continues to be an essential part of surfboard design, offering fins for all types of surfing.

The company’s fins are used in both competitive and recreational surfing worldwide. With decades of expertise, True Ames remains a trusted name in the surf industry. Their fins are a testament to the sport’s history and continual innovation.

Who is George Greenough?

George Greenough is a pioneering surfboard designer and surfer known for his innovative contributions to surfboard fins. He revolutionized fin design, collaborating with True Ames to create performance-oriented fins. Greenough’s work focused on enhancing maneuverability and control.

His influence can be seen in both modern boards and fin designs. Greenough’s unique perspective as a surfer shaped his approach to shaping fins. He was instrumental in refining surfboard fins for high-performance surfing. His collaboration with True Ames helped shape the industry. Greenough’s legacy in surfboard design continues to influence surfers today. His designs prioritized functionality, enabling better wave performance.