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 INA housing matched to the bearing type, bearings with a crowned outside surface compensate for shaft misalignments; see Compensation of misalignments.