Thanks to the compact length of the blade the 42/43 size in 37cm (14.5in) is the ideal fin for travel and for dives in warm waters.The orthopedic foot pocket with variable thickness provides superior comfort. The blade is constructed of Tecralene® and Thermoplastic rubber for extended durability.When water spills over the sides of the blade, it reduces thrust, and decreases efficiency. Mares design was derived from observing marine mammals such as manatees in their natural environment. When swimming they bend their tail to form a channel, which optimizes thrust. When proper channeling occurs, all of the displaced water contributes to thrust.The "Channel Thrust" technology maximizes the channeling of water and moves a much greater amount of water compared to other fins of the same size. The result is greater thrusting power with the same amount of effort. Mares latest development in "Channel Thrust" technology is the new "Superchannel" design. "Superchannel" further increases the high performance level of Mares fins.