DNA LOFT cushioning now extends throughout the midsole for an even smoother transition from heel to toe Air Mesh upper with 3D Fit Print technology offers snug fit and exceptional breathability BioMoGo DNA midsole brings heightened responsiveness to super-soft cushioning Guide Rails support system encourages natural motion of knees and hips, reducing chance of injury over time Tech Specs Brooks Adrenaline GTS 21 Weight: 9.1 oz Drop: 12 mm Category: Support Upper: Mesh Use: Running Surface: Road Custom pair: right shoe is wide width, left shoe is not Wear at interior lining Minimal wear on sole