Knowledge of the mechanical properties of aneurysm clips is essential for their safe use in cerebral aneurysm treatment. The clip consists of a coil spring, leg, crossover, and blades. In the present article, closing forces, antiscissoring systems, and opening width of clips were reviewed. Closing forces of clips linearly increased from tip to base of clip blades. Scissoring was likely to occur when occluding the neck of the aneurysm with only the tips of long clip blades. Opening width depended on the clip leg.