In regards to the back-to-back arrangement or "DB", axial loads in both directions and radial loads can be sustained. Due to the large distance between the effective load centers, this type is suitable when moments are applied but can not withstand larger rotational misalignments.
Angular contact ball bearings can also be arranged in a face-to-face arrangement or "DF". When compared to the "DB" arrangement, the distance between the effective load centers is small, so sustainable moment capacity is lower than the "DB" combination. On the other hand, this combination can handle more rotational misalignment and is used with housings that have less accuracy.