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.

Features and benefits
Accommodate static and dynamic misalignment
The bearings are self-aligning like spherical roller bearings or CARB bearings.
Excellent high-speed performance
Self-aligning ball bearings generate less friction than any other type of rolling bearing, which enables them to run cooler even at high speeds.
Minimum maintenance
Because of low heat generation, the bearing temperature is lower, leading to extended bearing life and maintenance intervals.
Low friction
Very loose conformity between balls and outer ring keeps friction and frictional heat at low levels.
Excellent light load performance
Self-aligning ball bearings have low minimum load requirements.
Low noise
Self-aligning ball bearings can reduce noise and vibration levels, for example, in fans.