The four-rope grab is mainly used with bridge or gantry cranes with two sets of lifting drums to grab all kinds of loose deposits,and perform operations such as loading, unloading, and transferring materials. Mainly supporting double girder bridge crane or double main girder gantry crane.According to the type of material and user requirements can be designed with teeth, parallel beam opening, underwater operation and other forms.Because the size of the bucket part of the grab is different, the capacity of the material captured is different, we usually divide the grab into four grades: light, medium, heavy and super heavy.