The Inov-8 TrailFly Ultra G-Series 300 Max is a revolutionary trail shoe featuring the world’s first graphene-enhanced foam: G-FLY.Pioneering a new way for cushioned ultra running shoes, TrailFly Ultra G 300 Max uses GRAPHENE-GRIP rubber for the world’s toughest trail traction, while the supportive upper fit adapts to the natural changes of the foot when running big miles. 8fNgPA.