Four-Point Contact Bearings correspond in structure to double-row angular contact ball bearings. In the axial direction, they are significantly narrower because of the single running groove. Offset centers of curvature on the arcuate raceways in the inner and outer rings result in the balls touching the race rings at four points under radial load. Consequently, four-point bearings should only be used where the axial load is predominant. If there are permanent radial loads, the four-point bearings are often combined with radial ball bearings.