GEL - The ASICS GEL system is based on a special kind of silicon that enables optimal shock absorption. GEL units are strategically placed in the midsole and designed to enable specific functions and positions whilst running Cuprothermo - ASICS advanced upper material designed to aid temperature regulation within the shoe through effective heat distribution and enhanced moisture management. Biomorphic Fit - Biomorphic technology is incorporated into the upper where the areas of highest deformation are found. This ensures a better fit, improved comfort, less risk of injury and enhanced performance. Enhanced Personal Heel Fit - A special foam heel construction that provides a perfect fit around the wearer's heel. 3M Reflective - Improved footwear visibility when running in low level light.