The C-clamp is made of 4.5mm thick stainless steel, strong without welding; with stainless steel hooks that can withstand 100 pounds of static gravity.The screw-compressor can be clamped in the range of 0-9/10 inches. Both the back and the bottom plate have a screw hole with a diameter of M8. You can install the stainless steel hook provided in the package The I-beam fixture are equipped with threaded clamp and spring washers to ensure that the object will not move after being clamped(Disc type threaded clamp) Sturdy clips can be used for temporary or permanent fixation of I-beam, board, hardware machinery, architectural decoration brackets, etc.It can also be used to hang some heavier objects under steel beams or ceilings