Inner ring is processed through heat treatment and precision machining, tolerance of dimension and geometric accuracy accords to the national standard. There is guiding chamfering at the two ends of the bearing race of the inner ring, which is convenient for installation. They are used for situation when the axis can not be processed with heat treatment and can not be treated as bearing race. When the needle rollers with inner ring and without ring are used together, normal working windage can be reached. Inner ring tolerance of lr is more than ir, terminal facet is not grinded, the price is low and they are usually used together with needle roller bearing with pressed outer ring. Soft shrink-wrap