Wire, length of metal that has been drawn out into a thread. Wire is usually flexible, circular in cross-section, and uniform in diameter. Wire diameters generally range from about 0.001 to 0.5 in (0.025–12.7 mm). To manufacture wire, a hot-rolled metal rod pointed at one end is coated with a lubricant, threaded through a tungsten, carbide, or diamond die, and attached to a drum called a draw block. The draw block is rotated and wire—its diameter (gauge) determined by the diameter of the die—is drawn until the entire metal rod is reduced to steel. Steel, iron, aluminum, copper, and bronze are the metals most widely used for wire making, although others, including gold, platinum, and silver, are used as well. Copper and aluminum are preferred for electrical wiring because they combine high ductility with low resistance to electric current.