Self-aligning ball bearings have two rows of balls and a common sphered raceway in the outer ring; this latter feature gives the bearing its self-aligning property, permitting minor angular misalignment of the shaft relative to the housing. They are therefore particularly suitable for applications where misalignment can arise from errors in mounting or shaft deflection.

HRB self-aligning ball bearings are available with cylindrical or tapered bore. Bearings with tapered bore can be supplied with suitable adapter sleeves.