This is the shimano dura ace 9000 36 hole front hub elite road racers demand the best dura ace components are precision engineered for ultimate performance and durability oversized axle has increased rigidity torsionally and laterally removing axle flex when under compression from the quick release thus improving rotational smoothness and durability labyrinth double contact sealing low friction seals effectively shut out water mud and dirt without affecting rotational smoothness borozo