Do you know about the Conductor Size ?
In the United States, smaller conductors are measured using the American Wire Gauge (AWG). With the gauge system, the higher the number is, the smaller the cable will be. For larger wires, circular mils are used. MCM sizes, also called kcmils (kilo-circular mils), are for even larger cables. One MCM is equivalent to one thousand circular mils.
For Britain and Canada, a system called the British Standard Wire Gauge (SWG) is the measurement system of choice. In other international countries, conductors are measured using their cross-section, which is given in square millimeters.
AWG - In the American Wire Gauge system, 36 AWG wire has a 0.0050” diameter. A 1000 (4/0) wire, has a .4600” diameter. There are also 39 gauge sizes in between. Although it seems like a strange system, it is designed so that the wire area approximately doubles for every three steps on the gauge scale.