Four-point contact ball bearings are single row angular contact ball bearings featuring raceways designed to accommodate thrust loads acting in both directions. At the same time, radial loads can be partly supported up to a proportional value of the axial load. This kind of bearing requires less space in axial direction than double row bearings do. Normally, single row four-point contact ball bearings supporting thrust loads in both directions are mounted together with another pure radial bearing. In this case the four-point contact ball bearings are mounted with radial clearance in the housing and they act as pure thrust bearings.