Hole saws and hole cutter kits include a selection of tool sizes, a pilot bit, and an arbor. They are used in a drill to make holes in wood, metal, and other materials. They have a narrow cutting edge that removes a ring of material from the workpiece, leaving the center of the material whole. Hole saws have a linear-edge blade welded to the rim. Hole cutters have individual cutting teeth, similar to a circular saw blade and are generally used to cut metal. Removing a ring of material while leaving the center whole reduces the time it takes to drill a hole and allows a larger hole to be cut using a handheld power drill.