This inner ring provides the mating raceway surface for needle roller bearings requiring a separate inner ring, with a cylindrical bore of 45.0 mm and a width of 25.0 mm. Net mass is 70.4 g, and the component is manufactured as a standalone ring, marked IR45X50X25-XL, intended to complete the bearing arrangement together with a matching needle roller and cage assembly. The cylindrical design allows mounting directly on a shaft, giving a hardened running surface where none exists on the shaft itself. Since it is supplied as a separate ring rather than a full bearing unit, the fit and surface finish of the shaft seat determine radial clearance and running accuracy, so shaft tolerance must be selected to suit the intended load and speed conditions.