Ball spline uses balls installed in the outer cylinder of the spline shaft to perform smooth liquid rolling and torque transmission in a precisely ground rolling groove. It adopts a unique contact point design with a larger contact angle (40 °). In addition to its high sensitivity, it can also significantly enhance the load capacity. Suitable for environments with high vibration impact load, high positioning accuracy requirements, and high-speed motion performance, it can also play an effective role in such environments. At the same time, even when used instead of linear ball bushings, the rated load of ball splines is more than ten times that of linear bushings due to the same shaft diameter. So it can make the design very compact, even under the action of cantilever load, torque, etc., it can be safely used and has high durability.