Cartridge hub design features both wheel bearings pre-set in one hub for optimum radial and lateral runout accuracy ABS applications will ship with the correct bearing to make sure ABS function is maintained Precision machined from radial forged 6061-T6 aluminum for maximum road durability No re-calibration will be required on linked brake models Lightweight coped design provides form and function. 21X3.5" F.7VALVE CHR ABS