The scissor grab extends the ends of the two jaw plates near the hinge point into a rope type force adding arm, and the two arms share a common one called the central hinge point. The opening action of the scissor grab depends on loosening the steel wire rope of the pulley block at the scissor arm and tightening the support rope. The closing action depends on tightening the steel wire rope of the pulley block and using the lever principle to increase the force, so that the jaw plate closes and grabs the material, and its closing torque gradually increases with the closing process. When grabbing the material, it is clean and does not leak material, It is mostly used in large bridge ship unloaders.