The 35mm stem was designed to reduce overall system weight while retaining the proven stiffness and performance. The stem itself is measurably stiffer than the 31.8mm offering and, although the system is a seemingly burlier build, the weight savings gained by the reduction in bar material actually makes the 35 system lighter overall. An impressively light, strong addition to your DH, Trail, Enduro, and even XC handlebar/stem combo.