27 Tech Reasons (SF-8)
When using the standard, flat fin, with the leg completely extended, there remains an angle of 27 degrees between the heel and the foot and the calf of the leg, causing a 10% loss of propulsion. Because the fin is angled below the body, during the kick phase, the body is pushed forward, instead of straight ahead. With the SF-8 fin, that 27 degree angle has been designed into the fin so the fin is parallel to the leg. This means that 100% of the energy expended during the kick phase is directed toward the propulsion of the diver.

Tusa developed the technology that has resulted in the creation of a robot that can replicate the motions of a human being. The robot is able to mimic the human under kick-bending at the ankle, knee and hip in one fluid motion. Using this robotic science, TUSA has been able to analyze the performance of the fins under several conditions. The robot is able to swim, through the water using kick variations, such as a large scissor kick with a slow repetition and vice versa. Using hightech instrumentation, this robot measures the energy expended during the kick and the propulsive force that is created using that energy.

To achieve maximum performance from this fin, use a small bent-knee kick with a light rhythm. This creates less strain on the leg muscles compared with traditional fins, reducing the diver's fatigue and subsequent air consumption.