Self aligning ball bearings 

Double row self-aligning ball bearings have a sphere raceway in the outer ring and a double raceway in the inner ring. This feature give the bearings their self-aligning property, permitting 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 from shaft deflection.

Double row self-aligning ball bearings are mainly used to carry radial loads and light axial loads, but cann't carry pure axial loads