As one of the standard accessories for the 50 series aluminum alloy sliding doors, it is fixed on both sides of the track and used in conjunction with the stop moving set fixed at the center of the track. When using it, first use a small drill bit to open the hole, then use a cross drill bit to expand the hole, and finally use a 10mm * 20mm screw to penetrate the wall for stable fixation. The entire installation process is simple and labor-saving, safe and efficient (front rubber bumper). The accessory spring has compression and shock absorption function, Preventing accidental derailment of the door during the sliding process not only ensures the sealing of the door, but also improves its safety and effective stopping.