The shimano slx mt66 wheelset uses a simple cup and cone bearing system with angular contact bearings to create a strong seal preventing the elements from slowing them down the smooth rotation of the bearings is complemented by the fast engaging freehub every 10 degrees making energy transfer simple and efficient the shimano slx mt66 wheelset features ust tubeless ready rims to give riders the options to reap the benefits of greater cornering grip less weight and greater comfort