Combination pliers have jaws designed to be especially versatile. The flat part can easily hold flat stock, while the rounded cut-out section is designed to hold rounded stock, such as small tubes and pipes, without crushing it. The gripping jaws of combination pliers can be used to compress materials. They can be used, for instance, to tighten a ferrule (a clamping collar used to fix parts together) or close chain links, such as those used to make jewellery or chainmail.