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. They are available open or sealed. The bearings are insensitive to angular misalignment of the shaft relative to the housing , which can be caused, for example, by shaft deflection.A self-aligning bearing is recommended when the alignment of the shaft and housing is difficult or when the shaft may bend during operation. Brda notes that similar to deep groove ball bearings, most self-aligning ball are for general use.

Self-Aligning Ball Bearings utilize two rows of balls and a common, concave outer race to automatically compensate for angular misalignment within a system. Misalignment, either from machining errors, assembly errors, or deflections, are a common risk in precise applications and Self-Aligning Ball Bearings present a viable solution.