Determined by their use within various industry sectors, these rods are made of various materials. The usual raw metals used are aluminum, bronze, silicon bronze, brass, copper, and even just special metal alloys. While aluminum varieties have good electrical and thermal conductivity, the brass varieties are notable for excellent high-temperature ductility, and low magnetic permeability. The copper threaded fastener is best termed as a great conductor of heat and electricity. Similarly, bronze and silicon bronze have their own special use.