The Mach 5 is the spurious offspring of Mach 4 and Mach Supersonic.  This shoe is incredibly light and snappy.  The Profly+ midsole gets a little stiffer as you transition through the forefoot providing a responsive toe off. The ride throughout is rockered and feels a touch softer thanks to the rubberized EVA outsole.  The upper is made of Creel jacquard engineered mesh so the toes can breath and be free.