Fins with world-class efficiency, making the most of your energy
3-Material Construction
In 1993 TUSA introduced the SF-7700 (IMPREX fin) to the market. This fin achieves
strong propulsion by combining two different materials to create an efficient water
channeling action. Since it first went on sale, over 600,000 divers have used it
worldwide. The IMPREX fin has been the undisputed leader in the plastic fin market.
Now, ten years later, it is moving to the next development stage.


 

The next generation IMPREX Tri-Ex fin utilizes three different materials.
First is the side rib (hard material), efficiently converting the energy of a kick into
propelling power. Second is the blade (medium-hard material), increasing the
efficiency of the water channel. Third is the soft pocket (soft material), enhancing
the fitting comfort of the boots. The designers expanded the blade angle theory that
had produced a strong propulsion force with only a light kick in the SF-8 model. A
fin testing robot was used to analyze on a computer the propulsion (speed) and the
electrical load when kicking. Tests were also run using real divers in a water
circulating pool.

These tests were repeated many times, the result being that the blade angle was
set at 20 degrees, the most comfortable for the diver. A smooth  
Even shape with no level differences
from the foot pocket to the blad 

shape was also created, with no level differences between the foot pocket and blade.
This means that compared with conventional products, less initial load
(energy) is required when first starting to kick.
The excellent fit and non-wasteful transmission of energy ensures that body
fatigue and air consumption is minimized.