A wheel bearing unit having a bearing including an outer race attachable to a wheel carrier and a rotating inner race attachable to a wheel hub. The outer race includes a first plurality of mounting openings for mounting a brake caliper assembly, and second plurality of mounting openings for mounting the outer race on the wheel carrier. The first and second pluralities of mounting openings are symmetrically arranged enabling the wheel bearing unit to be used on the left and right sides of the vehicle with the caliper assemblies in the same relative positions on both sides. The first mounting openings lie at a substantially larger radial distance from the axis of rotation of the bearing than the second mounting openings, whereby the second openings overlie a region of higher strength in the wheel carrier, and the first openings are clear of the region of higher strength.