There is a reason the True Ames Greenough 4-A Single Fin is the most iconic, functional and versatile single fin available... it works on just about anything! The Greenough 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.
Fin Size Detail
| Size | Height | Base | Area |
| 6.5" | 6.49" | 5.42" | 22.86"² |
| 7.0" | 7.09" | 5.67" | 24.89"² |
| 7.5" | 7.55" | 5.95" | 26.86"² |
| 8.0" | 8.11" | 6.09" | 28.85"² |
| 8.5" | 8.51" | 6.42" | 32.19"² |
| 9.0" | 9.14" | 6.93" | 36.13"² |
| 9.75" | 9.71" | 7.09" | 39.93"² |
| 10.0" | 10.08" | 7.42" | 43.85"² |
| 10.5" | 10.63" | 7.91" | 48.44"² |
The Smaller sizes (6" - 8") are phenomenal for 2 + 1 setups.
The larger sizes (8.5" - 10.5") are great to use for Single Fin setups.
Product Info
Cleanline Staff James Says:
"True Ames specializes in making fins, and they know what they’re doing. The 4-A will hold when needed but release when you’re ready to smack the lip like pro longboarder Taylor Jenson. I use the Greenough 4A as a single fin and a 2 +1. The 9” works great as a single fin for my 9’ TJ Pro. The Greenough 4-A is one of the most popular fins we sell at Cleanline and one of the most popular single fins used worldwide."
Cleanline Staff
There is a reason the True Ames Greenough 4-A Single Fin is the most iconic, functional and versatile single fin available... it works on just about anything! The Greenough 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.
Fin Size Detail
| Size | Height | Base | Area |
| 6.5" | 6.49" | 5.42" | 22.86"² |
| 7.0" | 7.09" | 5.67" | 24.89"² |
| 7.5" | 7.55" | 5.95" | 26.86"² |
| 8.0" | 8.11" | 6.09" | 28.85"² |
| 8.5" | 8.51" | 6.42" | 32.19"² |
| 9.0" | 9.14" | 6.93" | 36.13"² |
| 9.75" | 9.71" | 7.09" | 39.93"² |
| 10.0" | 10.08" | 7.42" | 43.85"² |
| 10.5" | 10.63" | 7.91" | 48.44"² |
The Smaller sizes (6" - 8") are phenomenal for 2 + 1 setups.
The larger sizes (8.5" - 10.5") are great to use for Single Fin setups.
Product Details
- Fin Type: Single Fin
- Small Sizes: 6.5" - 8"
- Large Sizes: 8.5" - 10.5"
- Fins in Set: One
- Fin Configuration: Single
- Construction: Solid Fiberglass
- Finish: Matte
Product Features
- Designed by George Greenough
- Moderate flex pattern and narrow tip
- Base has slight flare giving positive stability
Additional Info
A truly well-balanced fin...the full base coupled with the 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.
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.
Materials
A fin design is only as good as the materials used for construction. At True Ames, they carefully select the most well-suited types of fiberglass and wood for producing the highest quality fins available. In order to achieve the performance characteristics that have become the standard of solid fiberglass surf fins, True Ames uses E-glass. It is the most common type of fiberglass used in surfboard construction, and its qualities translate with great success into fin construction. E-glass has excellent flex characteristics and performance longevity, while featuring the bonus of outstanding color vibrancy that allows for the variety of colors we offer.
History & Origin
The man behind this revolutionary fin is George Greenough, whom the surf world is forever indebted to for his wave-riding performance innovations beginning in the '60s. Greenough ultimately paved the way from traditional logging to more progressive surfing in the pocket through the development of his Velo-Spoon kneeboard designs. To complement his kneeboards, Greenough found inspiration from mother nature for his fin templates through studying the tail fins of tuna–one of the fastest and most maneuverable fish in the ocean. The subsequent high-aspect ratio design he created allowed surfers to place themselves in more critical parts of the wave and execute more radical turns; it truly ushered in a new era of high performance capability. History lesson aside, the Greenough 4-A 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.
Warranty
This product is backed by a warranty from the manufacturer. Click below for details on the warranty policy for True Ames products.
Returns
If you are not 100% satisfied with your purchase you may return it for a refund, or exchange within 30 days of receiving your order.
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