Double-row angular contact ball bearings correspond, in their design and operation, to a pair of single-row angular contact ball bearings in a back-to-back arrangement, while requiring less axial space. They can operate at high speeds and are more suitable than deep groove ball bearings for supporting large axial forces in both directions. High-speed capability Accommodate relatively high radial loads, high axial loads in both directions and tilting moments Suitable where a stiff bearing arrangement is required Require less axial space than equivalent pair of single row angular contact ball bearings