1.Overload Protector can check the hydraulic pressure of cylinder inside the slider. 2.It can let the hydraulic pressure of cylinder released within 3/ 1000 seconds immediately. 3.When happening overload, it will release the electric signal and let the machine stop working. It can protect the press and die. 4.Air driven hydraulic pump can supply the hydraulic pressure of cylinder quickly. 5.Overload protector have pressure control valve, which can adjust hydraulic pressure caused by the oil temperature arising automatically.