4 - jaw crusher. rocksizer (single toggle up-thrust) or rocksledger (single toggle down-thrust) design. heavy duty reinforced fabricated welded steel plate body. high grade steel eccentric shaft. hydraulically adjusted jaw settings. 5 - power unit. either electric or diesel hydraulic caterpillar engine or similar, complete with hydraulic power.Apr 10, in a machine like the jaw crusher, toggle plates are a valuable component that essentially serve as a safety joint and fuse that is attached to the moving jaw. ... a modern solution to this problem has been the hydraulic toggle relief system that was conceived to replace the single-use toggle plates. ... franklin rock and recycle. 792 e. ingram.