Known as an iron-cake ball-joint, this model transmits power at constant speeds, capable of changing angles and extending and sliding, with the straight working guide of its inner and outer rollers slowly tilting along the axis of the differential. Attached to a bolt on the transmission, this model transmits power to the axle via the six bearings between inner and outer rollers. But since the axial travel of TJ and DOJ is short, the maximum working angle of this model is between 12 and 22 degrees, and suitable for only certain cars.