This is a separate cylindrical inner ring designed for use with needle roller bearings that operate without an integral inner ring. The bore diameter is 90.0 mm, width 26.0 mm, and net mass 0.292 kg. The cylindrical raceway surface provides a hardened running track for the rollers, replacing the shaft as the direct bearing surface. Because the inner ring is a separate component, it allows the raceway diameter and width to be matched precisely to the needle roller and cage assembly it is paired with. This construction lets the shaft itself be produced to a lower surface hardness requirement, since load-bearing contact takes place on the ring rather than directly on the shaft. Mounting requires correct axial and radial positioning relative to the mating roller and cage assembly to maintain proper contact geometry.