This inner ring provides the shaft-side raceway for needle roller bearing assemblies where a separate inner ring is required. It is precision machined to DIN 620, with a bore diameter of 6.0 mm, width of 10.0 mm and a net mass of 0.004 kg. A lubrication hole in the ring body allows grease or oil to reach the raceway from the shaft side, supporting the relubrication of the assembled bearing without dismantling it. The precision-machined raceway surface is intended to run together with needle rollers of matching dimensions, giving a defined fit and running accuracy consistent with DIN 620 tolerances. Because the ring is a separate component, it allows the raceway diameter and material properties to be matched independently of the shaft, which is useful where the shaft itself is not hardened or ground to bearing-raceway quality. The lubrication hole should be aligned with the corresponding supply passage during mounting to ensure the lubricant reaches the rolling contact.