Wood-cutting hole saw kits include a selection of hole saw sizes, an arbor, and a pilot bit. They are used to cut wood, plywood, and MDF. Hole saws have a cutting rim and hollow core to remove material while leaving a core of the material whole. This allows larger holes to be drilled faster using a handheld power drill than would be possible using a drill bit. The arbor holds the pilot bit and secures the hole saw in the drill. The pilot bit keeps the hole saw from walking or moving when it starts the cut.