These fixed blade fins are characterized by their thermo rubber foot-pocket and for the angle between foot-pocket and blade being 22 degrees (compared to traditional 15/17 degree). The use of thermo rubber of two different stiffness compounds increases comfort over normal foot-pockets. The 22 degree angle is the result of trying to optimize the power of the push through the water relative to effort. The blades are produced in a low modular polypropylene in two degrees of stiffness: Winter (grey) softer and Black (medium hardness).