Needle roller bearings with cylindrical roller of roller bearings, relative to its diameter, roller is thin and long. This is called needle roller. Although has a small cross-section, bearing still has high load capacity, therefore, especially suitable for radial space is limited. According to the use of different occasions, can be used without inner ring of the bearing or needle roller and cage components, at this time to suit the bearing surface of the surface of the shaft and the shell hole directly as inner and outer rolling bearing surface, in order to ensure the load capacity and operation performance and you have the same ring bearing, axis or shell hole hardness on the surface of the raceway, machining accuracy and surface quality should be as a bearing ring raceway. These bearings can bear radial load only.