Angular Contact (A/C) cartridge bearings specifically designed for hubs. In standard radial bearings, only 3 or 4 balls make contact during the load, at any given time. In Angular Contact (A/C) bearings, ALL balls are engaged and spread the force over a larger surface area, to decrease friction and minimize wear. Wheel play can be adjusted out of the hub providing a more stable wheel, and making it easier to adjust disc brakes while still spinning freely.