KDL series bearings utilize a single-row four-point contact ball arrangement, with each ball contacting the raceways at four distinct points. This geometry enables the bearing to simultaneously support axial loads in both directions, radial loads, and tilting moments within a single, compact row of rolling elements.

The defining characteristic of the KDL series is its lightweight, slim-profile design. The bearings are manufactured with a reduced ring cross-section compared to heavier-duty series, making them ideal for applications where weight reduction is a priority. The slim profile also contributes to a lower overall height for the towing equipment, maintaining a favorable center of gravity while reducing material costs and manufacturing complexity.

The bearings are equipped with integral mounting holes on both the inner and outer rings, enabling direct bolted attachment to the trailer chassis and the towing structure. This simplifies installation and eliminates the need for additional adaptor plates. The bearings are typically supplied with seals on both sides to prevent contamination from dirt, water, and debris commonly encountered in outdoor towing environments.