As the jaws of a clamp are commonly made from iron or steel, there is a risk of indenting the surface of a workpiece if its material is softer than that of the metal jaws. Jaw pads are, therefore, often used to prevent this from happening.
Jaw pads are plastic covers which are placed over the jaws, in order to prevent the clamp from damaging or marring the surface of the workpiece.
The pads can usually be purchased in sets so that they can be used on a number of clamps at the same time.