The midsole of the 909 is made up of ABZORB FL and ROCK STOP 2. ABZORB FL is New Balance's top of the line midsole foam that is an amazing blend of comfort and performance with DuPont Engage and isoprene rubber, providing the ultimate ride. ROCK STOP 2 is a flexible layer of high durometer EVA foam that is located between the outsole and the midsole. ROCK STOP 2 protects feet from rocks and shock, minimizes pressure, and disperses shock energy. |