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 ideal when the alignment of the shaft and housing is problematic and the shaft may bend. The outer ring has a spherical raceway with its center of curvature coinciding with the bearing. This allows the axis of the inner ring, balls and cage to deflect to some extent around the bearings center. The axial load capacity is low since the contact angle is small.