These sets of three matched super-precision angular contact ball bearings are available as universally matchable bearings or as preconfigured arrangements. Sets arranged in back-to-back and tandem, or face-to-face and tandem, are available in different preload classes and correct mounting results in preload within a predetermined range, without the need for shims or similar devices. Sets of three bearings paired in tandem need to be mounted against a single bearing, or another set of bearings in tandem, to achieve the desired preload. The bore and outside diameters of the bearings are matched to within a maximum of one-third of the permitted diameter tolerance, to provide better load distribution than single universally matchable bearings.