DFB Heavy-duty needle roller bearings have a machined and ground channel-shaped outer ring with a complement of needle rollers retained and guided by a cage. The thick outer ring provides maximum load capacity and shock resistance with a relatively small radial cross section. 

With the high-strength cage retaining and guiding the rollers, this design provides high speed and lubrication retention capability. A lubrication groove and hole in the O.D. facilitate relubrication through the outer ring. These bearings can be used with or without a machined and ground inner ring depending on the suitability of the shaft as a raceway surface.