We were surprised to learn that a lot of folks don't know what these are, which is why we featured them as this month's mystery item. Vise jaw caps are made of soft metal to protect the item they're holding. (Note all the dings on this pair.) Soft metal also allows the arms to be hammered around a vise to ensure a snug fit.

Jaw caps shouldn't be confused with jaw pads. They both serve the same purpose, but jaw pads affix to the interior of a vice and often are made of material other than metal. Can't afford a pair? Two blocks of wood serve the same purpose. Click here to enlarge the featured pic.