This is a separate cylindrical inner ring, designed as a component of a needle roller bearing assembly with a separable design. Bore diameter is 55.0 mm, width is 35.0 mm, and net mass is 120.5 g. The cylindrical raceway surface provides the running track for needle rollers or a needle roller cage assembly mounted on a shaft. Being a separate ring, it allows the shaft-side raceway to be replaced independently of the outer bearing components, which simplifies mounting and dismounting where a separable bearing arrangement is used. The inner ring must be matched with a compatible needle roller and cage assembly of corresponding dimensions to form a complete bearing position; it does not include integrated sealing or lubrication provisions, so sealing and lubrication method must be selected separately according to the application requirements.