Saucony Mirage 4 : With a redesigned upper that uses FlexFilm and minimal overlays, Saucony Mirage 4 running shoes deliver lightweight stability and a more ergonomic fit. PowerGrid replaces ProGrid in the heel to effectively center the foot and absorb impact for an exceptionally smooth and responsive ride. Just a touch of guidance completes the profile for an incredibly comfortable experience. Upper: FlexFilm™ lightweight yet strong material allows for fewer layers in the upper for a seamless, flexible feel. Padded tongue enhances comfort. Flat laces reduce irritation and pressure points. Mesh delivers breathable flexibility. Midsole: HydraMAX Collar Lining material combines superior moisture wicking properties with a plush feel for comfort. HRC Strobel Board delivers an additional 1.5mm of EVA in the strobel board to enhance the step-in comfort for an incredibly plush ride. PowerGrid heel insert effectively centers the foot, absorbs impact and distributes pressure, resulting in an exceptionally smooth and responsive ride. High-abrasion EVA foam is a lighter alternative to rubber in the midsole and outsole construction. TPU midfoot stabilizer supplies increased support. Removable perforated insole. Outsole: Blown rubber lightweight flexible material provides added cushioning while maintaining durability and a smooth ride. XT-900™ carbon rubber outsole material has outstanding abrasion and traction properties.