The bearings are available in 164 sizes in design variants NU, NJ and NUP. The bearing cages are available in roller-guided and outer ring-guided versions and are made from brass and polyamide, with pressed steel versions also available. In addition to radial clearance group CN (C0) as standard, group C3 models are also available. Special versions, for example traction motor bearings (SQ1) and electrically insulated bearings (SQ77) are available at short lead times.
The bearings are made from clean bearing steel to maximise their lifespan, this surface finish is claimed to reduce friction as well as lower the operating temperature. Due to the improved design of bearing guiding flanges of the NJ and NUP variants, the bearings can take up higher axial loads. Misalignments can be compensated through modified contact geometry and crowned inner raceways. Tighter tolerances for the roller sorting ensure a uniform load distribution.
