Mizuno Men's Wave Nirvana 7 Running Shoe 100% Synthetic Rubber sole SmoothRide Engineering utilizes the maximum energy efficiency properties of both flexibile and stiff footwear Dynamotion Fit technology relieves the stress the foot naturally places on footwear, eliminating distortion for the perfect fit Full-length midsole Mizuno Intercool ventilation system reduces heat and humidity build-up inside the shoe Gender Engineering philosophy maximizes performance by tailoring footwear to the separate needs of men and women Mizuno Wave technology combines cushioning and stability, two distinctly different elements that are both inherently necessary in great running shoes