Radial insert ball bearings are single row, rady-to-fit units comprising a solid outer ring, an inner ring extended on one or both sides, cages made from plastic or sheet steel and P, R, L or T seals. Bearings with an inner ring extended on both sides undergo less tilting of the inner ring and therefore run more smoothly. The outer ring has a crowned or cylindrical outside surface. In conjunction with an housing matched to the bearing type, bearings with a crowned outside surface compensate for shaft misalignments; see Compensation of misalignments. They are located on the shaft by means of an eccentric locking collar, grub screws in the inner ring, an adapter sleeve, drive slot or fit. Radial insert ball bearings are particularly easy to fit, suitable for drawn shafts of grade h6 to h9 and, with a few exceptions, can be relubricated. Some series with an eccentric locking collar and with grub screws in the inner ring are also available with an inch size bore.