Self aligning ball bearings have two rows of balls, a common sphered raceway in the outer ring and two deep uninterrupted raceway grooves in the inner ring. Self aligning ball bearings are insensitive to angular misalignment of the shaft relative to the housing, which can be caused, for example, by shaft deflection or housing deformations. Self aligning ball bearings are suitable for applications where the shaft relative to the housing bore is prone to angular misalignments. Under normal loads, depending on the dimensional series, the maximum permissible angular misalignment is approximately 2° to 4°. These bearings are available in open and sealed versions and inner rings with a cylindrical or tapered bore.