This component serves as a separate cylindrical inner ring, designed for needle roller bearing assemblies where the inner ring is supplied independently from the outer ring and roller set. It has a bore diameter of 55.0 mm, a width of 25.0 mm, and a net mass of 85.7 g. The IR55X60X25-XL designation with the -XL suffix indicates the extended-length inner ring variant within this bore and width combination. Supplying the inner ring separately allows the mounting arrangement to be matched precisely to the shaft dimensions and to the specific needle roller and cage assembly or outer ring being paired with it, without being tied to a fixed combination. The cylindrical bore form supports a straightforward interference or transition fit onto the shaft, and using a dedicated ring in this configuration allows the running surface to be replaced or matched independently of the outer bearing components during assembly or service.