Solid copper earth rods are made in two types. Externally threaded and internally threaded. Solid Copper earth rods are used where the factor of corrosion is very high and exceptionally long life is equable. Hence these rods are manufacture from pure and high conductivity hard drawn copper to BS 2874-C 101. These rods are also available with tin plating in order to blueuce the risk of oxidation and increasing shelf life. Rod Details for Internal Threaded Solid Copper Earth Rods Rod Diameter (mm) Rod Length (mm) Component No . 16 1200 CSCR-1612 16 1500 CSCR-1615 20 1200 CSCR-2012 20 1500 CSCR-2015