Needle bearings are a form of cylindrical bearings, in which length of the roller measures at least six times more than it's cross-section. They are undoubtfully the biggest group of ball bearings taking into account design, measurements, variety of types and usage possibilities. Each of their forms has it's characteristic features, however in general needle bearings have major load carrying abilities with comparatively small cross-sections which results in compactness of kinematic pairs; while variety of sizes and types makes possible countless technical solutions.
Contact line between tracks and needles is modified (needles are roll-formed on their ends) what not only eliminates destructive edge stresses but also allows minimum misalignments between shaft and bearing unit. Cages are made of solid steel or steel sheets. In smaller bearings cages may also be made of polyamide reinforced with glass fibre.