A tool with jaws is called a vise. It is typically used to hold objects securely in place while work is being done on them. Vises come in various sizes and styles, such as bench vises, pipe vises, and machinist vises.

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Vises, jacks and positioners.

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The expression "his hands are like vises" means that someone's hands have a strong or tight grip, like a vise -- a mechanical tool used to hold objects firmly in place. It suggests that the person has a powerful grip or is holding onto something securely.

The purpose of an engineering vise to clamp and hold an object in order to work with it. Most vises are permanently mounted on a work table.